EXECUTION COPY
                        RECONSTITUTED SERVICING AGREEMENT
         THIS RECONSTITUTED SERVICING AGREEMENT (this "Agreement"), entered into
as of the 1st day of August, 2005, by and between ▇▇▇▇▇▇ BROTHERS HOLDINGS INC.,
a Delaware corporation (the "Seller" or "▇▇▇▇▇▇ Brothers Holdings"), and ▇▇▇▇▇
FARGO BANK, NATIONAL ASSOCIATION, a national banking association (the
"Servicer"), and acknowledged by AURORA LOAN SERVICES LLC, a Delaware limited
liability company ("Aurora"), and HSBC BANK USA, NATIONAL ASSOCIATION, a
national banking association (the "Trustee"), recites and provides as follows:
                                    RECITALS
         WHEREAS, ▇▇▇▇▇▇ Brothers Bank, FSB (the "Bank") acquired certain
adjustable rate, conventional, first lien, residential mortgage loans from the
Servicer pursuant to the Seller's Warranties and Servicing Agreement between the
Seller and the Servicer, dated as of February 1, 2005 for Adjustable Rate
Mortgage Loans (2005-W08 and 2005-W10) (the "SWSA").
         WHEREAS, pursuant to an Assignment and Assumption Agreement, dated
August 1, 2005 (the "Assignment and Assumption Agreement") annexed as Exhibit F
hereto, the Seller acquired from the Bank all of the Bank's right, title and
interest in and to the mortgage loans currently serviced under the SWSA and
assumed for the benefit of each of the Servicer and the Bank the rights and
obligations of the Bank as owner of such mortgage loans pursuant to the SWSA.
         WHEREAS, the Seller has conveyed the mortgage loans identified on
Exhibit C hereto (the "Serviced Mortgage Loans") to Structured Asset Securities
Corporation, a Delaware special purpose corporation ("SASCO"), which in turn has
conveyed the Serviced Mortgage Loans to the Trustee, pursuant to a trust
agreement, dated as of August 1, 2005 (the "Trust Agreement"), among the
Trustee, Aurora, as master servicer ("Aurora", and, together with any successor
master servicer appointed pursuant to the provisions of the Trust Agreement, the
"Master Servicer") and SASCO.
         WHEREAS, the Serviced Mortgage Loans are currently being serviced by
the Servicer pursuant to the SWSA attached hereto as Exhibit B.
         WHEREAS, the Seller desires that the Servicer continue to service the
Serviced Mortgage Loans, and the Servicer has agreed to do so, subject to the
rights of the Seller and the Master Servicer to terminate the rights and
obligations of the Servicer hereunder as set forth herein and to the other
conditions set forth herein.
         WHEREAS, the Seller and the Servicer agree that the provisions of the
SWSA shall apply to the Serviced Mortgage Loans, except to the extent otherwise
provided herein and that this Agreement shall govern the Serviced Mortgage Loans
for so long as such Serviced Mortgage Loans remain subject to the provisions of
the Trust Agreement.
         WHEREAS, the Master Servicer and any successor master servicer shall be
obligated, among other things, to supervise the servicing of the Serviced
Mortgage Loans on behalf of the Trustee, and shall have the right, under certain
circumstances, to terminate the rights and obligations of the Servicer under
this Agreement.
         WHEREAS, the Seller and the Servicer intend that each of the Master
Servicer and the Trustee is an intended third party beneficiary of this
Agreement.
         NOW, THEREFORE, in consideration of the mutual agreements hereinafter
set forth and for other good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the Seller and the Servicer hereby
agree as follows:
                                    AGREEMENT
1. Definitions. Capitalized terms used and not defined in this Agreement,
including Exhibit A hereto and any provisions of the SWSA incorporated by
reference herein (regardless if such terms are defined in the SWSA), shall have
the meanings ascribed to such terms in the Trust Agreement.
2. Custodianship. The parties hereto acknowledge that ▇▇▇▇▇ Fargo Bank, National
Association will act as custodian of the Servicing Files for the Trustee
pursuant to a Custodial Agreement, dated August 1, 2005, between ▇▇▇▇▇ Fargo
Bank, National Association and the Trustee.
3. Servicing. The Servicer agrees, with respect to the Serviced Mortgage Loans,
to perform and observe the duties, responsibilities and obligations that are to
be performed and observed under the provisions of the SWSA, except as otherwise
provided herein and on Exhibit A hereto, and that the provisions of the SWSA, as
so modified, are and shall be a part of this Agreement to the same extent as if
set forth herein in full.
4. Trust Cut-off Date. The parties hereto acknowledge that by operation of
Section 4.05 and Section 5.01 of the SWSA, the remittance on September 19, 2005
to the Trust Fund is to include principal due after August 1, 2005 (the "Trust
Cut-off Date") plus interest, at the Mortgage Loan Remittance Rate collected
during the related Due Period exclusive of any portion thereof allocable to a
period prior to the Trust Cut-off Date, with the adjustments specified in
clauses (b), (c), (d) and (e) of Section 5.01 of the SWSA.
5. Master Servicing; Termination of Servicer. The Servicer, including any
successor servicer hereunder, shall be subject to the supervision of the Master
Servicer, which Master Servicer shall be obligated to ensure that the Servicer
services the Serviced Mortgage Loans in accordance with the provisions of this
Agreement. The Master Servicer, acting on behalf of the Trustee and the SARM
2005-18 Trust Fund (the "Trust Fund") created pursuant to the Trust Agreement,
shall have the same rights as the Seller under the SWSA to enforce the
obligations of the Servicer under the SWSA and the term "Purchaser" as used in
the SWSA in connection with any rights of the Purchaser shall refer to the Trust
Fund or, as the context requires, the Master Servicer acting in its capacity as
agent for the Trust Fund, except as otherwise specified in Exhibit A hereto. The
Master Servicer shall be entitled to terminate the rights and obligations of the
Servicer under this Agreement upon the failure of the Servicer to perform any of
its obligations under this Agreement, which failure results in an Event of
Default as provided in Section 10.01 of the SWSA. Notwithstanding anything
herein to the contrary, in no event shall the Master Servicer assume any of the
obligations of the Seller under the SWSA and in connection with the performance
of the Master Servicer's duties hereunder the parties and other signatories
hereto agree that the Master Servicer shall be entitled to all of the rights,
protections and limitations of liability afforded to the Master Servicer under
the Trust Agreement.
6. No Representations. Neither the Servicer nor the Master Servicer shall be
obligated or required to make any representations and warranties regarding the
characteristics of the Serviced Mortgage Loans (other than those representations
and warranties made by the Servicer in Section 3.02 of the SWSA hereby restated
as of the date of the SWSA) in connection with the transactions contemplated by
the Trust Agreement and issuance of the Certificates issued pursuant thereto.
                                       2
7. Notices. All notices and communications between or among the parties hereto
(including any third party beneficiary thereof) or required to be provided to
the Trustee shall be in writing and shall be deemed received or given when
mailed first-class mail, postage prepaid, addressed to each other party at its
address specified below or, if sent by facsimile or electronic mail, when
facsimile or electronic confirmation of receipt by the recipient is received by
the sender of such notice. Each party may designate to the other parties in
writing, from time to time, other addresses to which notices and communications
hereunder shall be sent.
         All notices required to be delivered to the Master Servicer under this
Agreement shall be delivered to the Master Servicer at the following address:
                  Aurora Loan Services LLC
                  ▇▇▇ ▇▇▇▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇
                  ▇▇▇▇▇▇▇▇▇, ▇▇  ▇▇▇▇▇
                  Mail Stop Code - 3195
                  Attn:  E. ▇▇▇▇ ▇▇▇▇▇▇▇▇▇▇ - ▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇▇
                         ▇▇▇▇ ▇▇▇▇-▇▇
                  Tel:   ▇▇▇-▇▇▇-▇▇▇▇
         All remittances required to be made to the Master Servicer under this
Agreement shall be made on a scheduled/scheduled basis to the following wire
account:
                  JPMorgan Chase Bank, N.A.
                  New York, New York
                  ABA#: ▇▇▇-▇▇▇-▇▇▇
                  Account Name: Aurora Loan Services LLC,
                                Master Servicing Payment Clearing Account
                  Account Number: 066-611059
                  Beneficiary: Aurora Loan Services LLC
                  For further credit to: SARM 2005-18
         All notices required to be delivered to the Trustee hereunder shall be
delivered to the Trustee at the following address:
                  HSBC Bank USA, National Association
                  ▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇▇
                  ▇▇▇ ▇▇▇▇, ▇▇▇ ▇▇▇▇ ▇▇▇▇▇
                  Attention: Issuer Services, SARM 2005-18
                  Telephone: ▇▇▇-▇▇▇-▇▇▇▇
                  Facsimile: ▇▇▇-▇▇▇-▇▇▇▇
         All notices required to be delivered to the Seller hereunder shall be
delivered to the Seller, at the following address:
                  ▇▇▇▇▇▇ Brothers Holdings Inc.
                  ▇▇▇ ▇▇▇▇▇▇▇ ▇▇▇▇▇▇, ▇▇▇ ▇▇▇▇▇
                  ▇▇▇ ▇▇▇▇, ▇▇▇ ▇▇▇▇  ▇▇▇▇▇
                  Attention: ▇▇▇▇▇▇ ▇▇▇▇▇▇
                  Telephone: ▇▇▇- ▇▇▇-▇▇▇▇
                  E-mail: ▇▇▇▇▇▇▇@▇▇▇▇▇▇.▇▇▇
                                       3
                  With a copy to:
                  Dechert, LLP
                  4000 ▇▇▇▇ Atlantic Tower
                  ▇▇▇▇ ▇▇▇▇ ▇▇▇▇▇▇
                  ▇▇▇▇▇▇▇▇▇▇▇▇, ▇▇ ▇▇▇▇▇
                  Attention: ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇, Esq.
         All notices required to be delivered to the Servicer hereunder shall be
delivered to its office at the address for notices as set forth in the SWSA.
8. Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, NOTWITHSTANDING NEW YORK OR
OTHER CHOICE OF LAW RULES TO THE CONTRARY.
9. Counterparts. This Agreement may be executed in any number of counterparts,
each of which when so executed shall be deemed to be an original, but all of
which counterparts shall together constitute but one and the same instrument.
                      [SIGNATURE PAGE IMMEDIATELY FOLLOWS]
                                       4
         Executed as of the day and year first above written.
                                        ▇▇▇▇▇▇ BROTHERS HOLDINGS INC.,
                                          as Seller
                                        By:
                                            ------------------------------------
                                            Name:  ▇▇▇▇▇ ▇▇▇▇▇▇▇
                                            Title: Authorized Signatory
                                        ▇▇▇▇▇ FARGO BANK, NATIONAL ASSOCIATION,
                                          as Servicer
                                        By:
                                            ------------------------------------
                                            Name:
                                            Title:
Acknowledged:
AURORA LOAN SERVICES LLC,
  as Master Servicer
By:
    ---------------------------------
    Name:  E. ▇▇▇▇ ▇▇▇▇▇▇▇▇▇▇
    Title: Executive Vice President
HSBC BANK USA, NATIONAL ASSOCIATION
  as Trustee
By:
    ---------------------------------
    Name:
    Title:
                                    EXHIBIT A
                            Modifications to the SWSA
1.       Unless otherwise specified herein, any provisions of the SWSA,
         including definitions, relating to (i) representations and warranties
         relating to the Mortgage Loans and not relating to the servicing of the
         Mortgage Loans, (ii) Mortgage Loan repurchase obligations, (iii) Whole
         Loan and Pass-Through Transfers and Reconstitution, and (iv)
         Assignments of Mortgage, shall be disregarded for purposes relating to
         this Agreement. The exhibits to the SWSA and all references to such
         exhibits shall also be disregarded.
2.       The definition of "Determination Date" in Article I is hereby amended
         as follows:
                  Determination Date: With respect to each Remittance Date, the
                  15th day of the month in which such Remittance Date occurs,
                  or, if such 15th day is not a Business Day, the succeeding
                  Business Day.
3.       A new definition of "Prepayment Charge" is added to Article I
         immediately following the definition of "PMI Policy" to read as
         follows:
                  Prepayment Charge: Any prepayment or yield maintenance fees,
                  penalties or charges to be paid by the Mortgagor in connection
                  with a Principal Prepayment on a Mortgage Loan.
4.       A new definition of "Prepayment Interest Shortfall Amount" is added to
         Article I immediately following the definition of "Prepayment Charge"
         to read as follows:
                  Prepayment Interest Shortfall Amount: With respect to any
                  Mortgage Loan that was subject to a Principal Prepayment in
                  full or in part during any Due Period, which Principal
                  Prepayment was applied to such Mortgage Loan prior to such
                  Mortgage Loan's Due Date in such Due Period, the amount of
                  interest (net of the related Servicing Fee for Principal
                  Prepayments in full only) that would have accrued on the
                  amount of such Principal Prepayment during the period
                  commencing on the date as of which such Principal Prepayment
                  was applied to such Mortgage Loan and ending on the day
                  immediately preceding such Due Date, inclusive.
5.       A new definition of "Realized Loss" is added to Article I immediately
         following the definition of "Rating Agencies" to read as follows:
                  Realized Loss: With respect to each Liquidated Mortgage Loan
                  (as defined in the Trust Agreement), an amount equal to (i)
                  the unpaid principal balance of such Mortgage Loan as of the
                  date of liquidation, minus (ii) Liquidation Proceeds received,
                  to the extent allocable to principal, net of amounts that are
                  reimbursable therefrom to the Master Servicer or the Company
                  with respect to such Mortgage Loan (other than Monthly
                  Advances of principal) including expenses of liquidation.
6.       The parties acknowledge that the fourth paragraph of Section 2.02
         (Books and Records; Transfers of Mortgage Loans) shall be inapplicable
         to this Agreement.
                                      A-1
7.       The parties acknowledge that Section 2.03 (Custodial Agreement;
         Delivery of Documents) shall be superceded by the provisions of the
         Custodial Agreement.
8.       Section 3.01(c) (No Conflicts) is hereby amended by deleting the words
         "the acquisition of the Mortgage Loans by the Company, the sale of the
         Mortgage Loans to the Purchaser".
9.       Section 3.01(f) (Ability to Perform) is hereby amended by deleting the
         second and third sentences thereof.
10.      Section 3.01(h) (No Consent Required) is hereby amended by deleting the
         words "or the sale of the Mortgage Loans".
11.      Section 3.01 (i) (Selection Process), Section 3.01(k) (Sale Treatment),
         Section 3.01(m) (No Brokers' Fees) and Section 3.01(n) (Fair
         Consideration) shall be inapplicable to this Agreement.
12.      Four new paragraphs are hereby added at the end of Section 3.03
         (Repurchase) to read as follows:
                           It is understood and agreed that the representations
                  and warranties set forth in Section 3.01 (a) through (h), (j)
                  and (l) are hereby restated as of the Closing Date and shall
                  survive the engagement of the Company to perform the servicing
                  responsibilities hereunder and the delivery of the Servicing
                  Files to the Company and shall inure to the benefit of the
                  Trustee, the Trust Fund and the Master Servicer. Upon
                  discovery by either the Company, the Master Servicer or the
                  Trustee of a breach of any of the foregoing representations
                  and warranties which materially and adversely affects the
                  ability of the Company to perform its duties and obligations
                  under this Agreement or otherwise materially and adversely
                  affects the value of the Mortgage Loans, the Mortgaged
                  Property or the priority of the security interest on such
                  Mortgaged Property or the interest of the Trustee or the Trust
                  Fund, the party discovering such breach shall give prompt
                  written notice to the other.
                           Within 60 days of the earlier of either discovery by
                  or notice to the Company of any breach of a representation or
                  warranty set forth in Section 3.01 which materially and
                  adversely affects the ability of the Company to perform its
                  duties and obligations under this Agreement or otherwise
                  materially and adversely affects the value of the Loans, the
                  Mortgaged Property or the priority of the security interest on
                  such Mortgaged Property, the Company shall use its best
                  efforts promptly to cure such breach in all material respects
                  and, if such breach cannot be cured, the Company shall, at the
                  Trustee's option, assign the Company's rights and obligations
                  under this Agreement (or respecting the affected Loans) to a
                  successor servicer selected by the Trustee with the prior
                  consent and approval of the Master Servicer. Such assignment
                  shall be made in accordance with Section 12.01.
                           In addition, the Company shall indemnify (from its
                  own funds) the Trustee, the Trust Fund and Master Servicer and
                  hold each of them harmless against any costs resulting from
                  any claim, demand, defense or assertion based on or grounded
                  upon, or resulting from, a breach of the Company's
                  representations and warranties contained in this Agreement. It
                  is understood and agreed that the remedies set forth in this
                  Section 3.01 constitute the sole remedies of the Master
                  Servicer, the Trust Fund and the Trustee respecting a breach
                  of the foregoing representations and warranties.
                                      A-2
                           Any cause of action against the Company relating to
                  or arising out of the breach of any representations and
                  warranties made in Section 3.01 shall accrue upon (i)
                  discovery of such breach by the Company or notice thereof by
                  the Trustee or Master Servicer to the Company, (ii) failure by
                  the Company to cure such breach within the applicable cure
                  period, and (iii) demand upon the Company by the Trustee or
                  the Master Servicer for compliance with this Agreement.
13.      Section 4.01 (Company to Act as Servicer) is hereby amended as follows:
(i) by deleting the first, second and third sentences of the second paragraph of
such section and replacing it with the following:
                           Consistent with the terms of this Agreement, the
                  Company may waive, modify or vary any term of any Mortgage
                  Loan or consent to the postponement of any such term or in any
                  manner grant indulgence to any Mortgagor if in the Company's
                  reasonable and prudent determination such waiver,
                  modification, postponement or indulgence is not materially
                  adverse to the Purchaser, provided, however, that unless the
                  Mortgagor is in default with respect to the Mortgage Loan or
                  such default is, in the judgment of the Company, imminent, the
                  Company shall not permit any modification with respect to any
                  Mortgage Loan that would change the Mortgage Interest Rate,
                  forgive the payment of principal or interest, reduce or
                  increase the outstanding principal balance (except for actual
                  payments of principal) or change the final maturity date on
                  such Mortgage Loan.
(ii) by adding the following to the end of the second paragraph of such section:
                  Promptly after the execution of any assumption, modification,
                  consolidation or extension of any Mortgage Loan, the Company
                  shall forward to the Master Servicer copies of any documents
                  evidencing such assumption, modification, consolidation or
                  extension. Notwithstanding anything to the contrary contained
                  in this Agreement, the Company shall not make or permit any
                  modification, waiver or amendment of any term of any Mortgage
                  Loan that would cause any REMIC created under the Trust
                  Agreement to fail to qualify as a REMIC or result in the
                  imposition of any tax under Section 860F(a) or Section 860G(d)
                  of the Code.
14.      Section 4.04 (Establishment of and Deposits to Custodial Account) is
         hereby amended as follows:
(a) the words "in trust for the Purchaser and/or subsequent purchasers of
Mortgage Loans, and various Mortgagors-P&I" in the fourth and fifth lines of the
first sentence of the first paragraph shall be replaced by the following: "in
trust for SARM 2005-18 Trust Fund and various Mortgagors".
(b) by amending clause (viii) to read as follows:
                           (viii)   the amount of any Prepayment Interest
                                    Shortfall Amount paid out of the Company's
                                    own funds without any right to reimbursement
                                    therefor;
15.      Section 4.05 (Permitted Withdrawals From Custodial Account) is hereby
         amended by replacing the last five lines of clause (ii) with the
         following:
                           the Trust Fund; provided however, that in the event
                  that the Company determines in good faith that any
                  unreimbursed Monthly Advances will not be recoverable from
                  amounts representing late recoveries of payments of principal
                  or interest respecting the particular Mortgage Loan as to
                  which such Monthly Advance was made or from Liquidation
                  Proceeds or Insurance Proceeds with respect to such Mortgage
                  Loan, the Company may reimburse itself for such amounts from
                  the Custodial Account, it being understood, in the case of any
                  such reimbursement, that the Company's right thereto shall be
                  prior to the rights of the Trust Fund;
                                      A-3
16.      Section 4.06 (Establishment of and Deposits to Escrow Account) shall be
         amended by deleting the words "Purchaser and/or subsequent purchasers
         of Residential Mortgage Loans, and various Mortgagors-T&I" in the
         fourth and fifth lines of the first sentence of the first paragraph,
         and replacing it with the following:
                  "in trust for SARM 2005-18 Trust Fund and various Mortgagors".
17.      Section 4.16 (Title, Management and Disposition of REO Property) is
         hereby amended by (i) adding two new paragraphs after the fourth
         paragraph thereof to read as follows:
                  In the event that the Trust Fund acquires any REO Property in
                  connection with a default or imminent default on a Mortgage
                  Loan, the Company shall dispose of such REO Property not later
                  than the end of the third taxable year after the year of its
                  acquisition by the Trust Fund unless the Company has applied
                  for and received a grant of extension from the Internal
                  Revenue Service to the effect that, under the REMIC Provisions
                  and any relevant proposed legislation and under applicable
                  state law, the applicable Trust REMIC may hold REO Property
                  for a longer period without adversely affecting the REMIC
                  status of such REMIC or causing the imposition of a federal or
                  state tax upon such REMIC. If the Company has received such an
                  extension, then the Company shall continue to attempt to sell
                  the REO Property for its fair market value for such period
                  longer than three years as such extension permits (the
                  "Extended Period"). If the Company has not received such an
                  extension and the Company is unable to sell the REO Property
                  within the period ending 3 months before the end of such third
                  taxable year after its acquisition by the Trust Fund or if the
                  Company has received such an extension, and the Company is
                  unable to sell the REO Property within the period ending three
                  months before the close of the Extended Period, the Company
                  shall, before the end of the three year period or the Extended
                  Period, as applicable, (i) purchase such REO Property at a
                  price equal to the REO Property's fair market value or (ii)
                  auction the REO Property to the highest bidder (which may be
                  the Company) in an auction reasonably designed to produce a
                  fair price prior to the expiration of the three-year period or
                  the Extended Period, as the case may be. The Trustee shall
                  sign any document or take any other action reasonably
                  requested by the Company which would enable the Company, on
                  behalf of the Trust Fund, to request such grant of extension.
                  Notwithstanding any other provisions of this Agreement, no REO
                  Property acquired by the Trust Fund shall be rented (or
                  allowed to continue to be rented) or otherwise used by or on
                  behalf of the Trust Fund in such a manner or pursuant to any
                  terms that would: (i) cause such REO Property to fail to
                  qualify as "foreclosure property" within the meaning of
                  Section 860G(a)(8) of the Code; or (ii) subject any Trust
                  REMIC to the imposition of any federal income taxes on the
                  income earned from such REO Property, including any taxes
                  imposed by reason of Sections 860F or 860G(c) of the Code,
                  unless the Company has agreed to indemnify and hold harmless
                  the Trust Fund with respect to the imposition of any such
                  taxes.
                                      A-4
         (ii) replacing the word "advances" in the sixth line of the fifth
         paragraph thereof with "Monthly Advances" and (iii) by adding the
         following to the end of such Section:
                  Prior to acceptance by the Company of an offer to sell any REO
                  Property, the Company shall notify the Master Servicer of such
                  offer in writing which notification shall set forth all
                  material terms of said offer (each a "Notice of Sale"). The
                  Master Servicer shall be deemed to have approved the sale of
                  any REO Property unless the Master Servicer notifies the
                  Company in writing, within five (5) days after its receipt of
                  the related Notice of Sale, that it disapproves of the related
                  sale, in which case the Company shall not proceed with such
                  sale.
18.      A new Section 4.24 is hereby added to read as follows:
         Section 4.24 Waiver of Prepayment Charges.
         The Servicer or any designee of the Servicer shall not waive any
Prepayment Charge with respect to any Mortgage Loan. If the Servicer or its
designee fails to collect a Prepayment Charge at the time of the related
prepayment of any Mortgage Loan subject to such Prepayment Charge, the Servicer
shall pay to the Purchaser at such time (by deposit to the Custodial Account) an
amount equal to the amount of the Prepayment Charge not collected.
Notwithstanding the above, the Servicer or its designee may waive a Prepayment
Charge without paying to the Purchaser the amount of such Prepayment Charge only
if the related prepayment is not the result of a refinancing by the Servicer or
its designee and such waiver (i) relates to a defaulted Mortgage Loan or a
reasonably foreseeable default, such waiver is standard and customary in
servicing similar mortgage loans to the Mortgage Loans, and such waiver, in the
reasonable judgment of the Servicer, would maximize recovery of total proceeds
from the Mortgage Loan, taking into account the amount of such Prepayment Charge
and the related Mortgage Loan, or (ii) relates to a Prepayment Charge the
collection of which, in the reasonable judgment of the Servicer, would be a
violation of applicable laws.
19.      Section 5.01 (Remittances) is hereby amended by replacing the word
         "second" with the word "first" in the second paragraph of such Section,
         and is further amended by adding the following after the second
         paragraph of such Section:
                           All remittances required to be made to the Master
                  Servicer shall be made to the following wire account or to
                  such other account as may be specified by the Master Servicer
                  from time to time:
                           JPMorgan Chase Bank, N.A.
                           New York, New York
                           ABA #: ▇▇▇-▇▇▇-▇▇▇
                           Account Name:  Aurora Loan Services LLC
                           Master Servicing Payment Clearing Account
                           Account Number: 066-611059
                           Beneficiary: Aurora Loan Services LLC
                           For further credit to: Aurora Loan Services 2005-18
20.      Section 5.02 (Statements to Purchaser) is hereby amended in its
         entirety to read as follows:
                  Section 5.02 Statements to Master Servicer.
                                      A-5
                           No later than 30 days upon request, the Company shall
                  deliver or cause to be delivered to the Master Servicer
                  executed copies of the custodial and escrow account
                  certifications or letter agreements pursuant to Sections 4.04
                  and 4.06.
                           Not later than the tenth calendar day of each month,
                  the Company shall furnish to the Master Servicer an electronic
                  file providing loan level accounting data for the period
                  ending on the last Business Day of the preceding month in the
                  format set forth in Exhibits D-1 and D-2 hereto (or in such
                  other format mutually agreed to between the Company and the
                  Master Servicer). The information required by Exhibit D-2 is
                  limited to that which is readily available to the Company and
                  is mutually agreed to by the Company and Master Servicer.
21.      Section 5.03 (Monthly Advances by Company) is hereby amended by
         deleting the last sentence of such Section.
22.      Section 6.04 (Annual Statements as to Compliance) is hereby amended by
         replacing the words "the Purchaser" in the first line with the words
         "the Master Servicer".
23.      Section 6.05 (Annual Independent Public Accountants' Servicing Report)
         is hereby amended by replacing the words "each Purchaser" in the third
         line with the words "the Master Servicer."
24.      Section 8.01 (Indemnification; Third Party Claims) is hereby amended in
         its entirety to read as follows:
                  The Company shall indemnify the Purchaser, the Trust Fund, the
                  Trustee and the Master Servicer and hold each of them harmless
                  against any and all claims, losses, damages, penalties, fines,
                  forfeitures, reasonable and necessary legal fees and related
                  costs, judgments, and any other costs, fees and expenses that
                  any of such parties may sustain in any way related to the
                  failure of the Company to perform its duties and service the
                  Mortgage Loans in strict compliance with the terms of this
                  Agreement. The Company immediately shall notify the Purchaser,
                  the Master Servicer and the Trustee or any other relevant
                  party if a claim is made by a third party with respect to this
                  Agreement or the Mortgage Loans, assume (with the prior
                  written consent of the indemnified party, which consent shall
                  not be unreasonably withheld or delayed) the defense of any
                  such claim and pay all expenses in connection therewith,
                  including counsel fees, and promptly pay, discharge and
                  satisfy any judgment or decree which may be entered against it
                  or any of such parties in respect of such claim. The Company
                  shall follow any written instructions received from the
                  Trustee in connection with such claim. The Company shall
                  provide the Trustee with a written report of all expenses and
                  advances incurred by the Company pursuant to this Section
                  8.01, and the Trustee from the assets of the Trust Fund
                  promptly shall reimburse the Company for all amounts advanced
                  by it pursuant to the preceding sentence except when the claim
                  is in any way relates to the failure of the Company to service
                  and administer the Mortgage Loans in strict compliance with
                  the terms of this Agreement or the gross negligence, bad faith
                  or willful misconduct of the Company.
25.      Section 10.01 (Events of Default) is hereby amended by:
(a)      changing any reference to "Purchaser" to "Master Servicer"
(b)      changing the reference to "five (5) days" to "two (2) Business Days" in
         clause (i); and
                                      A-6
(c)      amending subclause (vii) as follows: "the Company at any time is
         neither a ▇▇▇▇▇▇ ▇▇▇ or ▇▇▇▇▇▇▇ Mac approved servicer, and the Master
         Servicer has not terminated the rights and obligations of the Company
         under this Agreement and replaced the Company with a ▇▇▇▇▇▇ Mae or
         ▇▇▇▇▇▇▇ Mac approved servicer within 30 days of the absence of such
         approval; or".
26.      Section 10.02 (Waiver of Defaults) is hereby amended by changing the
         reference to "Purchaser" to "Master Servicer with the prior written
         consent of the Trustee".
27.      Section 11.01 (Termination) is hereby amended by restating subclause
         (ii) thereof to read as below and adding the following sentence after
         the first sentence of this Section 11.01:
                  (ii)     mutual consent of the Company and the Trustee in
                           writing, provided such termination is also acceptable
                           to the Master Servicer and the Rating Agencies.
                           At the time of any termination of the Company
                  pursuant to Section 11.01, the Company shall be entitled to
                  all accrued and unpaid Servicing Fees and unreimbursed
                  Servicing Advances and Monthly Advances; provided, however, in
                  the event of a termination for cause under Section 10.01
                  hereof, such unreimbursed amounts shall not be reimbursed to
                  the Company until such amounts are received by the Trust Fund
                  from the related Mortgage Loans.
28.      Section 11.02 (Termination Without Cause) is hereby amended by
         replacing the first reference to "The Purchaser" with "▇▇▇▇▇▇ Brothers
         Holdings (with the prior consent of the Trustee)" and by replacing all
         other references to "the Purchaser" with "▇▇▇▇▇▇ Brothers Holdings."
29.      Section 12.01 (Successor to Company) is hereby amended in its entirety
         to read as follows:
                           Simultaneously with the termination of the Company's
                  responsibilities and duties under this Agreement pursuant to
                  Sections 8.04, 10.01, 11.01(ii) or 11.02, the Master Servicer
                  shall, in accordance with the provisions of the Trust
                  Agreement (i) succeed to and assume all of the Company's
                  responsibilities, rights, duties and obligations under this
                  Agreement, or (ii) appoint a successor meeting the eligibility
                  requirements of this Agreement, and which shall succeed to all
                  rights and assume all of the responsibilities, duties and
                  liabilities of the Company under this Agreement with the
                  termination of the Company's responsibilities, duties and
                  liabilities under this Agreement. Any successor to the Company
                  that is not at that time a servicer of other mortgage loans
                  for the Trust Fund shall be subject to the approval of the
                  Master Servicer, the Purchaser, the Trustee and each Rating
                  Agency (as such term is defined in the Trust Agreement).
                  Unless the successor servicer is at that time a servicer of
                  other mortgage loans for the Trust Fund, each Rating Agency
                  must deliver to the Trustee a letter to the effect that such
                  transfer of servicing will not result in a qualification,
                  withdrawal or downgrade of the then-current rating of any of
                  the Certificates. In connection with such appointment and
                  assumption, the Master Servicer or the Purchaser, as
                  applicable, may make such arrangements for the compensation of
                  such successor out of payments on the Mortgage Loans as it and
                  such successor shall agree; provided, however, that no such
                  compensation shall be in excess of that permitted the Company
                  under this Agreement. In the event that the Company's duties,
                  responsibilities and liabilities under this Agreement should
                  be terminated pursuant to the aforementioned sections, the
                  Company shall discharge such duties and responsibilities
                  during the period from the date it acquires knowledge of such
                  termination until the effective date thereof with the same
                  degree of diligence and prudence which it is obligated to
                  exercise under this Agreement, and shall take no action
                                      A-7
                  whatsoever that might impair or prejudice the rights or
                  financial condition of its successor. The resignation or
                  removal of the Company pursuant to the aforementioned sections
                  shall not become effective until a successor shall be
                  appointed pursuant to this Section 12.01 and shall in no event
                  relieve the Company of the representations and warranties made
                  pursuant to Sections 3.01 and 3.02 and the remedies available
                  to the Trust Fund under Section 3.03 shall be applicable to
                  the Company notwithstanding any such resignation or
                  termination of the Company, or the termination of this
                  Agreement.
                           Within a reasonable period of time, but in no event
                  longer than 30 days of the appointment of a successor entity,
                  the Company shall prepare, execute and deliver to the
                  successor entity any and all documents and other instruments,
                  place in such successor's possession all Servicing Files, and
                  do or cause to be done all other acts or things necessary or
                  appropriate to effect the purposes of such notice of
                  termination. The Company shall cooperate with the Trustee and
                  the Master Servicer, as applicable, and such successor in
                  effecting the termination of the Company's responsibilities
                  and rights hereunder and the transfer of servicing
                  responsibilities to the successor servicer, including without
                  limitation, the transfer to such successor for administration
                  by it of all cash amounts which shall at the time be credited
                  by the Company to the Account or any Escrow Account or
                  thereafter received with respect to the Mortgage Loans.
                           Any successor appointed as provided herein shall
                  execute, acknowledge and deliver to the Trustee, the Company
                  and the Master Servicer an instrument accepting such
                  appointment, wherein the successor shall make an assumption of
                  the due and punctual performance and observance of each
                  covenant and condition to be performed and observed by the
                  Company under this Agreement, whereupon such successor shall
                  become fully vested with all the rights, powers, duties,
                  responsibilities, obligations and liabilities of the Company,
                  with like effect as if originally named as a party to this
                  Agreement. Any termination or resignation of the Company or
                  termination of this Agreement pursuant to Sections 8.04,
                  10.01, 11.01 or 11.02 shall not affect any claims that the
                  Master Servicer or the Trustee may have against the Company
                  arising out of the Company's actions or failure to act prior
                  to any such termination or resignation.
                           The Company shall deliver, within three (3) Business
                  Days of the appointment of a successor Servicer, the funds in
                  the Custodial Account and Escrow Account and all Collateral
                  Files, Credit Files and related documents and statements held
                  by it hereunder to the successor Servicer and the Company
                  shall account for all funds and shall execute and deliver such
                  instruments and do such other things as may reasonably be
                  required to more fully and definitively vest in the successor
                  all such rights, powers, duties, responsibilities, obligations
                  and liabilities of the Company.
                           Upon a successor's acceptance of appointment as such,
                  the Company shall notify the Trustee and Master Servicer of
                  such appointment in accordance with the notice procedures set
                  forth herein.
                           Except as otherwise provided in this Agreement, all
                  reasonable costs and expenses incurred in connection with any
                  transfer of servicing hereunder (whether as a result of
                  termination or removal of the Company or resignation of the
                  Company or otherwise), including, without limitation, the
                  costs and expenses of the Master Servicer or any other Person
                  in appointing a successor servicer, or of the Master Servicer
                  in assuming the responsibilities of the Company hereunder, or
                  of transferring the Servicing Files and the other necessary
                  data to the successor servicer shall be paid by the
                  terminated, removed or resigning Servicer from its own funds
                  without reimbursement.
                                      A-8
30.      Section 12.02 (Amendment) is hereby amended and restated in its
         entirety as follows:
                  Section 12.02 Amendment.
                           This Agreement may be amended from time to time by
                  written agreement signed by the Company and the Purchaser,
                  with the written consent of the Master Servicer and the
                  Trustee.
31.      Section 12.04 (Duration of Agreement) is hereby amended by deleting the
         last sentence thereof.
32.      Section 12.10 (Assignment by Purchaser) is hereby deleted in its
         entirety.
33.      Section 12.11 (Solicitation of Mortgagor) is hereby amended by
         replacing the words "the Purchaser" with "▇▇▇▇▇▇ Brothers Holdings" in
         each instance.
34.      A new Section 12.12 (Intended Third Party Beneficiaries) is hereby
         added to read as follows:
                           Notwithstanding any provision herein to the contrary,
                  the parties to this Agreement agree that it is appropriate, in
                  furtherance of the intent of such parties as set forth herein,
                  that the Master Servicer and the Trustee receive the benefit
                  of the provisions of this Agreement as intended third party
                  beneficiaries of this Agreement to the extent of such
                  provisions. The Company shall have the same obligations to the
                  Master Servicer and the Trustee as if they were parties to
                  this Agreement, and the Master Servicer and the Trustee shall
                  have the same rights and remedies to enforce the provisions of
                  this Agreement as if they were parties to this Agreement. The
                  Company shall only take direction from the Master Servicer (if
                  direction by the Master Servicer is required under this
                  Agreement) unless otherwise directed by this Agreement.
                  Notwithstanding the foregoing, all rights and obligations of
                  the Master Servicer and the Trustee hereunder (other than the
                  right to indemnification) shall terminate upon termination of
                  the Trust Agreement and of the Trust Fund pursuant to the
                  Trust Agreement.
35.      A new Section 12.13 (Officer's Certificate) is hereby added to read as
         follows:
                           On or before the last day of February of each year,
                  beginning with February 28, 2006, or in connection with any
                  additional ▇▇▇▇▇▇▇▇-▇▇▇▇▇ Certification required to be filed,
                  upon thirty days written request the Company, at its own
                  expense, will deliver to the Master Servicer a Servicing
                  Officer's Certificate, a form of which is attached hereto as
                  Exhibit E.
                                      A-9
                                    EXHIBIT B
                   Seller's Warranties and Servicing Agreement
                                See Exhibit 99.11
                                      B-1
                                    EXHIBIT C
                       Schedule of Serviced Mortgage Loans
                             [Intentionally Omitted]
                                      C-1
                                   EXHIBIT D-1
                   FORM OF MONTHLY DEFAULTED REMITTANCE ADVICE
FIELD NAME                 DESCRIPTION                                                           FORMAT
----------                 -----------                                                           ------
                                                                                           
INVNUM                     INVESTOR LOAN NUMBER                                                  Number no decimals
SERVNUM                    SERVICER LOAN NUMBER, REQUIRED                                        Number no decimals
BEGSCHEDBAL                BEGINNING SCHEDULED BALANCE FOR SCHED/SCHED                           Number two decimals
                           BEGINNING TRAIL BALANCE FOR ACTUAL/ACTUAL,
                           REQUIRED
SCHEDPRIN                  SCHEDULED PRINCIPAL AMOUNT FOR SCHEDULED/SCHEDULED                    Number two decimals
                           ACTUAL PRINCIPAL COLLECTED FOR ACTUAL/ACTUAL,
                           REQUIRED, .00 IF NO COLLECTIONS
CURT1                      CURTAILMENT 1 ▇▇▇▇▇▇, .▇▇ IF NOT APPLICABLE                           Number two decimals
CURT1DATE                  CURTAILMENT 1 DATE, BLANK IF NOT APPLICABLE                           DD-MMM-YY
CURT1ADJ                   CURTAILMENT 1 ADJUSTMENT, .00 IF NOT APPLICABLE                       Number two decimals
CURT2                      CURTAILMENT 2 ▇▇▇▇▇▇, .▇▇ IF NOT APPLICABLE                           Number two decimals
CURT2DATE                  CURTAILMENT 2 DATE, BLANK IF NOT APPLICABLE                           DD-MMM-YY
CURT2ADJ                   CURTAILMENT 2 ADJUSTMENT, .00 IF NOT APPLICABLE                       Number two decimals
LIQPRIN                    PAYOFF, LIQUIDATION PRINCIPAL, .00 IF NOT APPLICABLE                  Number two decimals
OTHPRIN                    OTHER PRINCIPAL, .00 IF NOT APPLICABLE                                Number two decimals
PRINREMIT                  TOTAL PRINCIPAL REMITTANCE AMOUNT, .00 IF NOT APPLICABLE              Number two decimals
INTREMIT                   NET INTEREST REMIT, INCLUDE PAYOFF INTEREST,                          Number two decimals
                           .00 IF NOT APPLICABLE
TOTREMIT                   TOTAL REMITTANCE AMOUNT, .00 IF NOT APPLICABLE                        Number two decimals
ENDSCHEDBAL                ENDING SCHEDULED BALANCE FOR SCHEDULED/SCHEDULED                      Number two decimals
                           ENDING TRIAL BALANCE FOR ACTUAL/ACTUAL
                           .00 IF PAIDOFF, LIQUIDATED OR FULL CHARGEOFF
ENDACTBAL                  ENDING TRIAL BALANCE                                                  Number two decimals
                           .00 IF PAIDOFF, LIQUIDATED OR FULL CHARGEOFF
ENDDUEDATE                 ENDING ACTUAL DUE DATE, NOT LAST PAID INSTALLMENT                     DD-MMM-YY
ACTCODE                    60 IF PAIDOFF, BLANK IF NOT APPLICABLE                                Number no decimals
ACTDATE                    ACTUAL PAYOFF DATE, BLANK IF NOT APPLICABLE                           DD-MMM-YY
INTRATE                    INTEREST RATE, REQUIRED                                               Number seven decimals
                                                                                                 Example .0700000 for 7.00%
SFRATE                     SERVICE FEE RATE, REQUIRED                                            Number seven decimals
                                                                                                 Example .0025000 for .25%
PTRATE                     PASS THRU RATE, REQUIRED                                              Number seven decimals
                                                                                                 Example .0675000 for 6.75%
PIPMT                      P&I CONSTANT, REQUIRED                                                Number two decimals
                           .00 IF PAIDOFF
                                     ▇-▇-▇
                                   ▇▇▇▇▇▇▇ ▇-▇
                ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇ FOR MONTHLY DEFAULTED LOAN REPORT
------------------------------------------------------------------------------------------------------------------------------------
DATA FIELD        FORMAT                                                                DATA DESCRIPTION
------------------------------------------------------------------------------------------------------------------------------------
                                                                                  
% of MI coverage  NUMBER(6,5)                                                           The percent of coverage provided by the PMI
                                                                                        company in the event of loss on a defaulted
                                                                                        loan.
------------------------------------------------------------------------------------------------------------------------------------
Actual MI claim   DATE(MM/DD/YYYY)                                                      Actual date that the claim was submitted to
filed date                                                                              the PMI company.
------------------------------------------------------------------------------------------------------------------------------------
Actual bankruptcy DATE(MM/DD/YYYY)                                                      Actual date that the bankruptcy petition is
start date                                                                              filed with the court.
------------------------------------------------------------------------------------------------------------------------------------
Actual MI claim   NUMBER(15,2)                                                          The amount of the claim that was filed by
amount filed                                                                            the servicer with the PMI company.
------------------------------------------------------------------------------------------------------------------------------------
Actual discharge  DATE(MM/DD/YYYY)                                                      Actual date that the Discharge Order is
date                                                                                    entered in the bankruptcy docket.
------------------------------------------------------------------------------------------------------------------------------------
Actual due date   DATE(MM/DD/YYYY)                                                      Actual due date of the next outstanding
                                                                                        payment amount due from the mortgagor.
------------------------------------------------------------------------------------------------------------------------------------
Actual eviction   DATE(MM/DD/YYYY)                                                      Actual date that the eviction proceedings
complete date                                                                           are completed by local counsel.
------------------------------------------------------------------------------------------------------------------------------------
Actual eviction   DATE(MM/DD/YYYY)                                                      Actual date that the eviction proceedings
start date                                                                              are commenced by local counsel.
------------------------------------------------------------------------------------------------------------------------------------
Actual first      DATE(MM/DD/YYYY)                                                      Actual date that foreclosure counsel filed
legal date                                                                              the first legal action as defined by state
                                                                                        statute.
------------------------------------------------------------------------------------------------------------------------------------
Actual redemption DATE(MM/DD/YYYY)                                                      Actual date that the foreclosure redemption
end date                                                                                period expires.
------------------------------------------------------------------------------------------------------------------------------------
Bankruptcy        VARCHAR2(2) 7=Chapter 7 filed  11=Chapter 11 filed                    Chapter of bankruptcy filed.
chapter                      12=Chapter 12 filed 13=Chapter 13 filed
------------------------------------------------------------------------------------------------------------------------------------
Bankruptcy flag   VARCHAR2(2) Y=Active Bankruptcy  N=No Active Bankruptcy               Servicer defined indicator that identifies
                                                                                        that the property is an asset in an active
                                                                                        bankruptcy case.
------------------------------------------------------------------------------------------------------------------------------------
Bankruptcy Case   VARCHAR2(15)                                                          The court assigned case number of the
Number                                                                                  bankruptcy filed by a party with interest in
                                                                                        the property.
------------------------------------------------------------------------------------------------------------------------------------
MI claim amount   NUMBER(15,2)                                                          The amount paid to the servicer by the PMI
paid                                                                                    company as a result of submitting an MI
                                                                                        claim.
------------------------------------------------------------------------------------------------------------------------------------
                                      D-2-1
------------------------------------------------------------------------------------------------------------------------------------
DATA FIELD        FORMAT                                                                DATA DESCRIPTION
------------------------------------------------------------------------------------------------------------------------------------
                                                                                  
MI claim funds    DATE(MM/DD/YYYY)                                                      Actual date that funds were received from
received date                                                                           the PMI company as a result of transmitting
                                                                                        an MI claim.
------------------------------------------------------------------------------------------------------------------------------------
Current loan      NUMBER(10,2)                                                          Current unpaid principal balance of the loan
amount                                                                                  as of the date of reporting to Aurora Master
                                                                                        Servicing.
------------------------------------------------------------------------------------------------------------------------------------
Date FC sale      DATE(MM/DD/YYYY)                                                      Date that the foreclosure sale is scheduled
scheduled                                                                               to be held.
------------------------------------------------------------------------------------------------------------------------------------
Date relief/      DATE(MM/DD/YYYY)                                                      Actual date that the dismissal or relief
dismissal granted                                                                       from stay order is entered by the bankruptcy
                                                                                        court.
------------------------------------------------------------------------------------------------------------------------------------
Date REO offer    DATE(MM/DD/YYYY)                                                      Actual date of acceptance of an REO offer.
accepted
------------------------------------------------------------------------------------------------------------------------------------
Date REO offer    DATE(MM/DD/YYYY)                                                      Actual date of receipt of an REO offer.
received
------------------------------------------------------------------------------------------------------------------------------------
Delinquency value NUMBER(10,2)                                                          Value obtained typically from a BPO prior to
                                                                                        foreclosure referral not related to loss
                                                                                        mitigation activity.
------------------------------------------------------------------------------------------------------------------------------------
Delinquency value VARCHAR2(15) BPO=Broker's Price Opinion  Appraisal=Appraisal          Name of vendor or management company that
source                                                                                  provided the delinquency valuation amount.
------------------------------------------------------------------------------------------------------------------------------------
Delinquency value DATE(MM/DD/YYYY)                                                      Date that the delinquency valuation amount
date                                                                                    was completed by vendor or property
                                                                                        management company.
------------------------------------------------------------------------------------------------------------------------------------
Delinquency flag  VARCHAR2(2) Y=90+ delinq. Not in FC, Bky or Loss mit                  Servicer defined indicator that identifies
                              N=Less than 90 days delinquent                            that the loan is delinquent but is not
                                                                                        involved in loss mitigation, foreclosure,
                                                                                        bankruptcy or REO.
------------------------------------------------------------------------------------------------------------------------------------
Foreclosure flag  VARCHAR2(2) Y=Active foreclosure   N=No active foreclosure            Servicer defined indicator that identifies
                                                                                        that the loan is involved in foreclosure
                                                                                        proceedings.
------------------------------------------------------------------------------------------------------------------------------------
Corporate expense NUMBER(10,2)                                                          Total of all cumulative expenses advanced by
balance                                                                                 the servicer for non-escrow expenses such as
                                                                                        but not limited to: FC fees and costs,
                                                                                        bankruptcy fees and costs, property
                                                                                        preservation and property inspections.
------------------------------------------------------------------------------------------------------------------------------------
Foreclosure       DATE(MM/DD/YYYY)                                                      Actual date that the loan was referred to
attorney referral                                                                       local counsel to begin foreclosure
date                                                                                    proceedings.
------------------------------------------------------------------------------------------------------------------------------------
                                      D-2-2
------------------------------------------------------------------------------------------------------------------------------------
DATA FIELD        FORMAT                                                                DATA DESCRIPTION
------------------------------------------------------------------------------------------------------------------------------------
                                                                                  
Foreclosure       NUMBER(15,2)                                                          Value obtained during the foreclosure
valuation amount                                                                        process. Usually as a result of a BPO and
                                                                                        typically used to calculate the bid.
------------------------------------------------------------------------------------------------------------------------------------
Foreclosure       DATE(MM/DD/YYYY)                                                      Date that foreclosure valuation amount was
valuation date                                                                          completed by vendor or property management
                                                                                        company.
------------------------------------------------------------------------------------------------------------------------------------
Foreclosure       VARCHAR2(80) BPO=Broker's Price Opinion   Appraisal=Appraisal         Name of vendor or management company that
valuation source                                                                        provided the foreclosure valuation amount.
------------------------------------------------------------------------------------------------------------------------------------
FHA 27011A        DATE(MM/DD/YYYY)                                                      Actual date that the FHA 27011A claim was
transmitted date                                                                        submitted to HUD.
------------------------------------------------------------------------------------------------------------------------------------
FHA 27011 B       DATE(MM/DD/YYYY)                                                      Actual date that the FHA 27011B claim was
transmitted date                                                                        submitted to HUD.
------------------------------------------------------------------------------------------------------------------------------------
VA LGC/ FHA Case  VARCHAR2(15)                                                          Number that is assigned individually to the
number                                                                                  loan by either HUD or VA at the time of
                                                                                        origination.  The number is located on the
                                                                                        Loan Guarantee Certificate (LGC) or the
                                                                                        Mortgage Insurance Certificate (MIC).
------------------------------------------------------------------------------------------------------------------------------------
FHA Part A funds  DATE(MM/DD/YYYY)                                                      Actual date that funds were received from
received date                                                                           HUD as a result of transmitting the 27011A
                                                                                        claim.
------------------------------------------------------------------------------------------------------------------------------------
Foreclosure       DATE(MM/DD/YYYY)                                                      Actual date that the foreclosure sale was
actual sale date                                                                        held.
------------------------------------------------------------------------------------------------------------------------------------
Servicer loan     VARCHAR2(15)                                                          Individual number that uniquely identifies
number                                                                                  loan as defined by servicer.
------------------------------------------------------------------------------------------------------------------------------------
Loan type         VARCHAR2(2) 1=FHA Residential       2=VA Residential                  Type of loan being serviced generally
                              3=Conventional w/o PMI  4=Commercial                      defined by the existence of certain types of
                              5=FHA Project           6=Conventional w/PMI              insurance. (ie: FHA, VA, conventional
                              7=HUD 235/265           8=Daily Simple Interest Loan      insured, conventional uninsured, SBA, etc.)
                              9=Farm Loan             U=Unknown
                              S=Sub prime
------------------------------------------------------------------------------------------------------------------------------------
Loss mit approval DATE(MM/DD/YYYY)                                                      The date determined that the servicer and
date                                                                                    mortgagor agree to pursue a defined loss
                                                                                        mitigation alternative.
------------------------------------------------------------------------------------------------------------------------------------
Loss mit flag     VARCHAR2(2) Y=Active loss mitigation  N=No active loss mitigation     Servicer defined indicator that identifies
                                                                                        that the loan is involved in completing a
                                                                                        loss mitigation alternative.
------------------------------------------------------------------------------------------------------------------------------------
                                      D-2-3
------------------------------------------------------------------------------------------------------------------------------------
DATA FIELD        FORMAT                                                                DATA DESCRIPTION
------------------------------------------------------------------------------------------------------------------------------------
                                                                                  
Loss mit removal  DATE(MM/DD/YYYY)                                                      The date that the mortgagor is denied loss
date                                                                                    mitigation alternatives or the date that the
                                                                                        loss mitigation alternative is completed
                                                                                        resulting in a current or liquidated loan.
------------------------------------------------------------------------------------------------------------------------------------
Loss mit type     VARCHAR2(2)  L=Loss Mitigation                 LT=Litigation pending  The defined loss mitigation alternative
                               NP=Pending non-performing sale    CH=Charge off          identified on the loss mit approval date.
                               DI=Deed in lieu                   FB=Forbearance plan
                               MO=Modification                   PC=Partial claim
                               SH=Short sale                     VA=VA refunding
------------------------------------------------------------------------------------------------------------------------------------
Loss mit value    NUMBER(10,2)                                                          Value obtained typically from a BPO prior to
                                                                                        foreclosure sale intended to aid in the
                                                                                        completion of loss mitigation activity.
------------------------------------------------------------------------------------------------------------------------------------
Loss mit value    DATE(MM/DD/YYYY)                                                      Name of vendor or management company that
date                                                                                    provided the loss mitigation valuation
                                                                                        amount.
------------------------------------------------------------------------------------------------------------------------------------
Loss mit value    VARCHAR2(15)  BPO=Broker's Price Opinion  Appraisal=Appraisal         Date that the loss mitigation valuation
source                                                                                  amount was completed by vendor or property
                                                                                        management company.
------------------------------------------------------------------------------------------------------------------------------------
MI certificate    VARCHAR2(15)                                                          A number that is assigned individually to
number                                                                                  the loan by the PMI company at the time of
                                                                                        origination. Similar to the VA LGC/FHA Case
                                                                                        Number in purpose.
------------------------------------------------------------------------------------------------------------------------------------
LPMI Cost         NUMBER(7,7)                                                           The current premium paid to the PMI company
                                                                                        for Lender Paid Mortgage Insurance.
------------------------------------------------------------------------------------------------------------------------------------
Occupancy status  VARCHAR2(1)   O=Owner occupied    T=Tenant occupied                   The most recent status of the property
                                U=Unknown           V=Vacant                            regarding who if anyone is occupying the
                                                                                        property.  Typically a result of a routine
                                                                                        property inspection.
------------------------------------------------------------------------------------------------------------------------------------
First Vacancy     DATE(MM/DD/YYYY)                                                      The date that the most recent occupancy
date/Occupancy                                                                          status was determined. Typically the date
status date                                                                             of the most recent property inspection.
------------------------------------------------------------------------------------------------------------------------------------
Original loan     NUMBER(10,2)                                                          Amount of the contractual obligations (ie:
amount                                                                                  note and mortgage/deed of trust).
------------------------------------------------------------------------------------------------------------------------------------
Original value    NUMBER(10,2)                                                          Appraised value of property as of
amount                                                                                  origination typically determined through the
                                                                                        appraisal process.
------------------------------------------------------------------------------------------------------------------------------------
                                      D-2-4
------------------------------------------------------------------------------------------------------------------------------------
DATA FIELD        FORMAT                                                                DATA DESCRIPTION
------------------------------------------------------------------------------------------------------------------------------------
                                                                                  
Origination date  DATE(MM/DD/YYYY)                                                      Date that the contractual obligations (ie:
                                                                                        note and mortgage/deed of trust) of the
                                                                                        mortgagor was executed.
------------------------------------------------------------------------------------------------------------------------------------
FHA Part B funds  DATE(MM/DD/YYYY)                                                      Actual date that funds were received from
received date                                                                           HUD as a result of transmitting the 27011B
                                                                                        claim.
------------------------------------------------------------------------------------------------------------------------------------
Post petition due DATE(MM/DD/YYYY)                                                      The post petition due date of a loan
date                                                                                    involved in a chapter 13 bankruptcy.
------------------------------------------------------------------------------------------------------------------------------------
Property          VARCHAR2(2) 1=Excellent           2=Good                              Physical condition of the property as most
condition                     3=Average             4=Fair                              recently reported to the servicer by vendor
                              5=Poor                6=Very poor                         or property management company.
------------------------------------------------------------------------------------------------------------------------------------
Property type     VARCHAR2(2)       1=Single family          2=Town house               Type of property secured by mortgage such
                  3=Condo           4=Multifamily            5=Other                    as: single family, 2-4 unit, etc.
                  6=Prefabricated   B=Commercial             C=Land only
                  7=Mobile home     U=Unknown                D=Farm
                  A=Church          P=PUD                    R=Row house
                  O=Co-op           M=Manufactured housing   24=2-4 family
                  CT=Condotel       MU=Mixed use
------------------------------------------------------------------------------------------------------------------------------------
Reason for        VARCHAR2(3) 001=Death of principal mtgr 02=Illness of principal mtgr  Cause of delinquency as identified by
default               003=Illness of mtgr's family member                               mortgagor.
                      004=Death of mtgr's family member   005=Marital difficulties
                      006=Curtailment of income           007=Excessive obligations
                      008=Abandonment of property         009=Distant employee transfer
                      011=Property problem                012=Inability to sell property
                      013=Inability to rent property      014=Military service
                      015=Other                           016=Unemployment
                      017=Business failure                019=Casualty loss
                      022=Energy-Environment costs        023=Servicing problems
                      026=Payment adjustment              027=Payment dispute
                      029=Transfer ownership pending      030=Fraud
                      031=Unable to contact borrower      INC=Incarceration
------------------------------------------------------------------------------------------------------------------------------------
                                      D-2-5
------------------------------------------------------------------------------------------------------------------------------------
DATA FIELD        FORMAT                                                                DATA DESCRIPTION
------------------------------------------------------------------------------------------------------------------------------------
                                                                                  
REO repaired      NUMBER(10,2)                                                          The projected value of the property that is
value                                                                                   adjusted from the "as is" value assuming
                                                                                        necessary repairs have been made to the
                                                                                        property as determined by the
                                                                                        vendor/property management company.
------------------------------------------------------------------------------------------------------------------------------------
REO list price    NUMBER(15,2)                                                          The most recent listing/pricing amount as
adjustment amount                                                                       updated by the servicer for REO properties.
------------------------------------------------------------------------------------------------------------------------------------
REO list price    DATE(MM/DD/YYYY)                                                      The most recent date that the servicer
adjustment date                                                                         advised the agent to make an adjustment to
                                                                                        the REO listing price.
------------------------------------------------------------------------------------------------------------------------------------
REO value (as is) NUMBER(10,2)                                                          The value of the property without making any
                                                                                        repairs as determined by the vendor/property
                                                                                        management company.
------------------------------------------------------------------------------------------------------------------------------------
REO actual        DATE(MM/DD/YYYY)                                                      The actual date that the sale of the REO
closing date                                                                            property closed escrow.
------------------------------------------------------------------------------------------------------------------------------------
REO flag          VARCHAR2(7)     Y=Active REO       N=No active REO                    Servicer defined indicator that identifies
                                                                                        that the property is now Real Estate Owned.
------------------------------------------------------------------------------------------------------------------------------------
REO original      DATE(MM/DD/YYYY)                                                      The initial/first date that the property was
list date                                                                               listed with an agent as an REO.
------------------------------------------------------------------------------------------------------------------------------------
REO original      NUMBER(15,2)                                                          The initial/first price that was used to
list price                                                                              list the property with an agent as an REO.
------------------------------------------------------------------------------------------------------------------------------------
REO net sales     NUMBER(10,2)                                                          The actual REO sales price less closing
proceeds                                                                                costs paid. The net sales proceeds are
                                                                                        identified within the HUD1 settlement
                                                                                        statement.
------------------------------------------------------------------------------------------------------------------------------------
REO sales price   NUMBER(10,2)                                                          Actual sales price agreed upon by both the
                                                                                        purchaser and servicer as documented on the
                                                                                        HUD1 settlement statement.
------------------------------------------------------------------------------------------------------------------------------------
REO scheduled     DATE(MM/DD/YYYY)                                                      The date that the sale of the REO property
close date                                                                              is scheduled to close escrow.
------------------------------------------------------------------------------------------------------------------------------------
REO value date    DATE(MM/DD/YYYY)                                                      Date that the vendor or management company
                                                                                        completed the valuation of the property
                                                                                        resulting in the REO value (as is).
------------------------------------------------------------------------------------------------------------------------------------
REO value source  VARCHAR2(15)   BPO=Broker's Price Opinion                             Name of vendor or management company that
                                 Appraisal=Appraisal                                    provided the REO value (as is).
------------------------------------------------------------------------------------------------------------------------------------
                                      D-2-6
------------------------------------------------------------------------------------------------------------------------------------
DATA FIELD        FORMAT                                                                DATA DESCRIPTION
------------------------------------------------------------------------------------------------------------------------------------
                                                                                  
Repay first due   DATE(MM/DD/YYYY)                                                      The due date of the first scheduled payment
date                                                                                    due under a forbearance or repayment plan
                                                                                        agreed to by both the mortgagor and
                                                                                        servicer.
------------------------------------------------------------------------------------------------------------------------------------
Repay next due    DATE(MM/DD/YYYY)                                                      The due date of the next outstanding payment
date                                                                                    due under a forbearance or repayment plan
                                                                                        agreed to by both the mortgagor and
                                                                                        servicer.
------------------------------------------------------------------------------------------------------------------------------------
Repay plan        DATE(MM/DD/YYYY)                                                      The servicer defined date upon which the
broken/                                                                                 servicer considers that the plan is no
reinstated/closed                                                                       longer in effect as a result of plan
date                                                                                    completion or mortgagor's failure to remit
                                                                                        payments as scheduled.
------------------------------------------------------------------------------------------------------------------------------------
Repay plan        DATE(MM/DD/YYYY)                                                      The date that both the mortgagor and
created date                                                                            servicer agree to the terms of a forbearance
                                                                                        or repayment plan.
------------------------------------------------------------------------------------------------------------------------------------
SBO loan number   NUMBER(9)                                                             Individual number that uniquely identifies
                                                                                        loan as defined by Aurora Master Servicing.
------------------------------------------------------------------------------------------------------------------------------------
Escrow balance/   NUMBER(10,2)                                                          The positive or negative account balance
advance balance                                                                         that is dedicated to payment of hazard
                                                                                        insurance, property taxes, MI, etc. (escrow
                                                                                        items only)
------------------------------------------------------------------------------------------------------------------------------------
Title approval    DATE(MM/DD/YYYY)                                                      The actual date that the title approval was
letter received                                                                         received as set forth in the HUD title
date                                                                                    approval letter.
------------------------------------------------------------------------------------------------------------------------------------
Title package     DATE(MM/DD/YYYY)                                                      The actual date that the title package was
HUD/VA date                                                                             submitted to either HUD or VA.
------------------------------------------------------------------------------------------------------------------------------------
VA claim funds    DATE(MM/DD/YYYY)                                                      The actual date that funds were received by
received date                                                                           the servicer from the VA for the expense
                                                                                        claim submitted by the servicer.
------------------------------------------------------------------------------------------------------------------------------------
VA claim          DATE(MM/DD/YYYY)                                                      The actual date that the expense claim was
submitted date                                                                          submitted by the servicer to the VA.
------------------------------------------------------------------------------------------------------------------------------------
VA first funds    NUMBER(15,2)                                                          The amount of funds received by the servicer
received amount                                                                         from VA as a result of the specified bid.
------------------------------------------------------------------------------------------------------------------------------------
VA first funds    DATE(MM/DD/YYYY)                                                      The date that the funds from the specified
received date                                                                           bid were received by the servicer from the
                                                                                        VA.
------------------------------------------------------------------------------------------------------------------------------------
VA ▇▇▇ submitted  DATE(MM/DD/YYYY)                                                      Actual date that the Notice of Election to
date                                                                                    Convey was submitted to the VA.
------------------------------------------------------------------------------------------------------------------------------------
                                      D-2-7
------------------------------------------------------------------------------------------------------------------------------------
DATA FIELD        FORMAT                                                                DATA DESCRIPTION
------------------------------------------------------------------------------------------------------------------------------------
                                                                                  
Zip Code          VARCHAR2(5)                                                           US postal zip code that corresponds to
                                                                                        property location.
------------------------------------------------------------------------------------------------------------------------------------
FNMA Delinquency  VARCHAR2(3)         09=Forbearance          17=Preforeclosure sale    The code that is electronically reported to
status code       24=Drug seizure     26=Refinance            27=Assumption             FNMA by the servicer that reflects the
                  28=Modification     29=Charge-off           30=Third-party sale       current defaulted status of a loan. (ie: 65,
                  31=Probate          32=Military indulgence  43=Foreclosure            67, 43 or 44)
                  44=Deed-in-lieu     49=Assignment           61=Second lien
                  62=VA no-bid        63=VA Refund            64=VA Buydown
                  65=Ch. 7 bankruptcy 66=Ch. 11 bankruptcy    67=Ch. 13 bankruptcy
------------------------------------------------------------------------------------------------------------------------------------
FNMA delinquency  VARCHAR2(3) 001=Death of principal mtgr 002=Illness of principal mtgr The code that is electronically reported to
reason code       003=Illness of mtgr's family member 004=Death of mtgr's family member FNMA by the servicer that describes the
                  005=Marital difficulties            006=Curtailment of income         circumstance that appears to be the primary
                  007=Excessive obligations           008=Abandonment of property       contributing factor to the delinquency.
                  009=Distant employee transfer       011=Property problem
                  012=Inability to sell property      013=Inability to rent property
                  014=Military service                015=Other
                  016=Unemployment                    017=Business failure
                  019=Casualty loss                   022=Energy-Environment costs
                  023=Servicing problems              026=Payment adjustment
                  027=Payment dispute                 029=Transfer ownership pending
                  030=Fraud                           031=Unable to contact  borrower
                  INC=Incarceration
------------------------------------------------------------------------------------------------------------------------------------
Suspense balance  NUMBER(10,2)                                                          Money submitted to the servicer, credited to
                                                                                        the mortgagor's account but not allocated to
                                                                                        principal, interest, escrow, etc.
------------------------------------------------------------------------------------------------------------------------------------
Restricted escrow NUMBER(10,2)                                                          Money held in escrow by the mortgage company
balance                                                                                 through completion of repairs to property.
------------------------------------------------------------------------------------------------------------------------------------
Investor number   NUMBER (10,2)                                                         Unique number assigned to a group of loans
                                                                                        in the servicing system.
------------------------------------------------------------------------------------------------------------------------------------
                                     D-2-8
                                    EXHIBIT E
                              ANNUAL CERTIFICATION
Re:  Structured Adjustable Rate Mortgage Loan Trust, Mortgage Pass-Through
     Certificates, Series 2005-18
     ---------------------------------------------------------------------
I, [identify the certifying individual], a [title] of ▇▇▇▇▇ Fargo Bank, National
Association (the "Servicer"), certify to [identify the company submitting to
SEC], and its officers, directors, agents and affiliates (in its role as
[identify role] the "Sarbanes Certifying Party"), and with the knowledge and
intent that they will rely upon this certification, that:
1.   Based on my knowledge, the information relating to the Mortgage Loans and
     the servicing thereof submitted by the Servicer to the Sarbanes Certifying
     Party which is used in connection with preparation of the reports on Form
     8-K and the annual report on Form 10-K filed with the SEC with respect to
     each transaction listed on the attached Exhibit A, taken as a whole, does
     not contain any untrue statement of a material fact or omit to state a
     material fact necessary to make the statements made, in light of the
     circumstances under which such statements were made, not misleading as of
     the date of this certification;
2.   The servicing information required to be provided to the Sarbanes
     Certifying Party by the Servicer under the relevant servicing agreements
     has been provided to the Sarbanes Certifying Party;
3.   I am responsible for reviewing the activities performed by the Servicer
     under the relevant servicing agreements and based upon the review required
     by the relevant servicing agreements, and except as disclosed in the Annual
     Statement of Compliance, the Annual Independent Public Accountant's
     Servicing Report and all servicing reports, officer's certificates and
     other information relating to the servicing of the Mortgage Loans submitted
     to the Sarbanes Certifying Party, the Servicer has, as of the date of this
     certification fulfilled its obligations under the relevant servicing
     agreements; and
4.   I have disclosed to the Sarbanes Certifying Party all significant
     deficiencies relating to the Servicer's compliance with the minimum
     servicing standards in accordance with a review conducted in compliance
     with the Uniform Single Attestation Program for Mortgage Bankers or similar
     standard as set forth in the relevant servicing agreements.
5.   The Servicer shall indemnify and hold harmless the Sarbanes Certifying
     Party and its officers, directors, agents and affiliates from and against
     any losses, damages, penalties, fines, forfeitures, reasonable legal fees
     and related costs, judgments and other costs and expenses arising out of or
     based upon a breach by the Servicer or any of its officers, directors,
     agents or affiliates of its obligations under this Certification or the
     negligence, bad faith or willful misconduct of the Servicer in connection
     therewith. If the indemnification provided for herein is unavailable or
     insufficient to hold harmless the Sarbanes Certifying Party, then the
     Servicer agrees that it shall contribute to the amount paid or payable by
     the Sarbanes Certifying Party as a result of the losses, claims, damages or
     liabilities of the Sarbanes Certifying Party in such proportion as is
     appropriate to reflect the relative fault of the Sarbanes Certifying Party
     on the one hand and the Servicer on the other in connection with a breach
     of the Servicer's obligations under this Certification or the Servicer's
     negligence, bad faith or willful misconduct in connection therewith.
                                      E-1
         IN WITNESS WHEREOF, I have hereunto signed my name and affixed the seal
of the Servicer.
Dated:                                By:
      -------------------                   -----------------------------------
                                      Name:
                                            -----------------------------------
                                      Title:
                                              ---------------------------------
                                      E-2
                                    Exhibit F
                       Assignment and Assumption Agreement
                             [Intentionally Omitted]
                                      F-1