Mortgage Loan Purchase Agreement
                        --------------------------------

                  Mortgage Loan Purchase Agreement (the "AGREEMENT"), dated as
of December 23, 2003 between Washington Mutual Mortgage Securities Corp. (the
"SELLER") and ABN AMRO Mortgage Corporation (the "PURCHASER").

                  Subject to the terms and conditions of this Agreement, the
Seller agrees to sell and the Purchaser agrees to purchase certain mortgage
loans (the "MORTGAGE LOANS") as described herein and as identified on the
Mortgage Loan Schedule defined in SECTION 2 hereof. The Mortgage Loans will be
purchased on a servicing retained basis.

                  Now, therefore, in consideration of the premises and the
mutual agreements set forth herein, the parties agree as follows:

SECTION 1.   PURCHASE AND SALE OF THE MORTGAGE LOANS.

         (a) Pursuant to the terms hereof and upon satisfaction of the
conditions set forth herein, the Seller agrees to sell and the Purchaser agrees
to purchase, Mortgage Loans having the general characteristics set forth in this
Agreement and specifically identified on the Mortgage Loan Schedule, for the
Purchase Price set forth below in SECTION 3(A) hereof and having an aggregate
principal balance on and as of the date of such Mortgage Loan Schedule (the
"CUT-OFF DATE") of approximately $354,678,057 after deduction of principal
payments due on or before the Cut-Off Date (which amount may vary plus or minus
5% thereof), or such other aggregate principal balance as agreed by the
Purchaser and the Seller as evidenced by the actual aggregate principal balance
of the Mortgage Loans accepted by the Purchaser on the Closing Date (as defined
below).

         (b) Subject to mutual agreement between the Purchaser and the Seller,
the closing for the purchase and sale of the Mortgage Loans shall take place on
December 23, 2003 (the "CLOSING DATE") at the office of Purchaser's counsel in
New York, New York or such other place as the parties shall agree.

SECTION 2.   MORTGAGE LOAN SCHEDULE.

         Attached to this Agreement as Schedule 1 is a listing of the Mortgage
Loans evidenced by promissory notes, mortgage notes or other evidence of
indebtedness (the "MORTGAGE NOTES") evidencing the indebtedness of one or more
obligors (each a "MORTGAGOR") and the related mortgages, deeds of trust or other
instruments securing a Mortgage Loan (the "MORTGAGES") to be purchased by and
delivered to the Purchaser on the Closing Date (as such may be amended prior to
the Closing Date by mutual agreement of the parties) (the "MORTGAGE LOAN
SCHEDULE"). The "Mortgage Loan Schedule" as of the Closing Date shall refer to
the Mortgage Loan Schedule as delivered on the Cut- Off Date related to such
Mortgage Loans to be purchased by or on behalf of the Purchaser pursuant




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to the terms of this Agreement. The Mortgage Loan Schedule shall contain as to
each Mortgage Loan listed thereon, at a minimum, the Mortgage Loan information
indicated on SCHEDULE 2 hereto.

SECTION 3.   PURCHASE PRICE.

         (a) In exchange for the Mortgage Loans, on the Closing Date, the
Purchaser shall transfer to the Seller by wire transfer in immediately available
funds the purchase price (the "Purchase Price") which is equal to * % multiplied
by the principal balance thereof as of the Cut-Off Date plus any accrued and
unpaid interest thereon from the Cut-Off Date to the Closing Date.

         (b) The Purchaser shall be entitled to all scheduled payments of
principal and interest due with respect to the Mortgage Loans after the Cut-Off
Date, and all other recoveries of principal and interest collected after the
Cut-Off Date (other than in respect of principal and interest on the Mortgage
Loans due on or before the Cut-Off Date). The Seller shall be entitled to all
scheduled payments of principal and interest due with respect to the Mortgage
Loans on or before the Cut-Off Date, and all other recoveries of principal and
interest collected on or before the Cut-Off Date (other than in respect of
principal and interest on the Mortgage Loans due after the Cut-Off Date). The
principal balance of each Mortgage Loan as of the Cut-Off Date is determined
after deduction of payments of principal due on or before the Cut-Off Date
whether or not collected. Therefore, payments of scheduled principal and
interest prepaid for a date due following the Cut-Off Date shall not be deducted
from the principal balance as of the Cut-Off Date but such prepaid amounts shall
belong to and be promptly remitted to the Purchaser.

SECTION 4.   EXAMINATION OF MORTGAGE FILES.

         Prior to the Closing Date, the Seller will have made files for each
Mortgage Loan, that consist at least of the documents listed on SCHEDULE 3
attached hereto (with respect to each Mortgage Loan, a "Mortgage File", and
collectively, the "MORTGAGE FILES"), available to the Purchaser or its agents,
for examination at the Seller's offices or such other location as shall
otherwise be agreed upon by the Purchaser and the Seller. The Purchaser may
purchase all or part of the Mortgage Loans with or without conducting any
partial or complete examination. The fact that the Purchaser or its agents have
conducted or have failed to conduct any partial or complete examination of the
Mortgage Files shall not affect the Purchaser's rights under this Agreement,
including, but not limited to, the rights to demand repurchase, substitution or
other relief as provided in this Agreement.

SECTION 5.   TRANSFER OF MORTGAGE LOANS; POSSESSION OF MORTGAGE FILES.

         (a) On the Closing Date, subject to the satisfaction of the terms and
conditions hereof, the Seller shall sell, transfer, assign, set over and
otherwise convey to the Purchaser, without recourse, but subject to the terms of
this Agreement, all right, title and interest of the Seller in and to the
Mortgage Loans (excluding the servicing rights related thereto) and all proceeds
thereof,

----------------------
         *  Provided upon request by Washington Mutual Mortgage Securities Corp.


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wherever located, including without limitation, all amounts in respect of
principal and interest received or receivable with respect to Mortgage Loan
payments due after the Cut-Off Date (and including scheduled payments of
principal and interest due after the Cut-Off Date but received by the Seller on
or before the Cut-Off Date, but not including payments of principal and interest
due on the Mortgage Loans on or before the Cut-Off Date), together with the
proceeds of any related mortgage insurance policies. Such transfer shall be made
directly to the Purchaser in accordance with the letter delivered to the Seller
by the Purchaser attached hereto as EXHIBIT A (the "INSTRUCTION LETTER"). The
Seller's records will accurately reflect the sale of each Mortgage Loan to the
Purchaser.

         (b) The ownership of each Mortgage Loan (excluding the related
servicing rights) and the related Mortgage Note, the Mortgage and the contents
of the related Mortgage File shall be, upon satisfaction of SECTION 3(A) hereof,
vested in the Purchaser and the ownership of all records and documents with
respect to such Mortgage Loan prepared by or which come into the possession of
the Seller shall immediately vest in the Purchaser and shall be retained and
maintained by the Seller at the will and for the benefit of the Purchaser in a
custodial capacity only. The Seller shall deliver to the Purchaser or its agent
in accordance with the instructions set forth in EXHIBIT A, simultaneously with
the execution and delivery of this Agreement or prior to the Closing Date, all
of the documents pertaining to each Mortgage Loan.

         (c) The transfer of the Mortgage Loans as described herein shall be
absolute and is intended by the parties to be a sale. In the event that a court
deems the conveyance set forth herein not to constitute a sale, the Seller shall
have granted to the Purchaser and the Trustee (as defined in the Pooling and
Servicing Agreement, dated as of December 1, 2003 (the "POOLING AND SERVICING
AGREEMENT"), among the Purchaser, as depositor, Washington Mutual Mortgage
Securities Corp., as servicer, and U.S. Bank National Association, as trustee) a
first priority security interest in the Mortgage Loans and in the proceeds
thereof of any kind or nature whatsoever, and in the proceeds of any related
insurance policies, subject to the satisfaction or waiver of the conditions set
forth in SECTION 11 hereof, and shall take, or shall cause to have been taken,
all steps necessary prior to the Closing Date to perfect such security interest
in the Purchaser.

SECTION 6.   BOOKS AND RECORDS.

         On the Closing Date, following the sale of the Mortgage Loans to the
Purchaser, title to each Mortgage and the related Mortgage Note shall be
transferred to the Purchaser or its assignee in accordance with this Agreement.
All rights arising out of the Mortgage Loans after the Cut-Off Date including,
but not limited to, any and all funds received on or in connection with a
Mortgage Loan and due after the Cut-Off Date shall be received and held by the
Seller in a custodial capacity for the benefit of the Purchaser or its assignee
as the owner of the Mortgage Loans in accordance herewith and shall be delivered
or caused to be delivered by the Seller to the Purchaser or its assignee on or
immediately following the Closing Date. Any funds received by the Seller, the
Purchaser or the Servicer (as defined in the Pooling and Servicing Agreement)
after the Cut-Off Date but due prior


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to the Cut-Off Date shall remain the property of the Seller and shall be
promptly remitted to the Seller.

SECTION 7.   FURTHER ACTIONS; FINANCING STATEMENTS.

         (a) In furtherance of the provisions of SECTION 5(C) hereof, the Seller
agrees to take or cause to be taken such further actions to execute, deliver and
file or cause to be executed, delivered and filed, such further documents and
instruments (including, without limitation, any UCC financing statements) as may
be necessary, or as the Purchaser may reasonably request, in order to perfect
and maintain the security interest created pursuant to said section and to
otherwise fully effectuate the purposes, terms and conditions of this Agreement,
and the Purchaser shall cooperate in any such action.

         (b) The Seller shall: (i) promptly execute, deliver, and file any
financing statements, amendments, continuation statements, assignments,
certificates and other documents with respect to such security interest as may
be necessary to enable the Purchaser to perfect or to maintain the perfection of
such security interest, each in form and substance satisfactory to the
Purchaser; and the Seller hereby grants to the Purchaser, subject to the
satisfaction or waiver of the conditions set forth in SECTION 11 hereof, the
right, at the Purchaser's option, to file any or all such financing statements,
amendments, continuation statements, assignments, certificates and other
documents pursuant to the UCC and otherwise without its signature and hereby
irrevocably appoints the Purchaser, subject to the satisfaction or waiver of the
conditions set forth in SECTION 11 hereof, as its attorney-in-fact to execute,
deliver and file any such financing statements, amendments, continuation
statements, assignments, certificates and other documents in the Seller's name
and to perform all other acts which the Purchaser deems appropriate to perfect
or to maintain the perfection of the security interest; and (ii) notify the
Purchaser within five (5) days after the occurrence of any of the following: (A)
any change in the Seller's corporate name or any trade name; (B) any change in
the Seller's location of its chief executive office or principal place of
business; and (C) any merger or consolidation or other change in Seller's
identity or material change in its corporate structure.

SECTION 8.   REPRESENTATIONS, WARRANTIES AND AGREEMENTS OF SELLER.

         (a) The Seller hereby represents and warrants to the Purchaser as of
the Closing Date (or such other date as is specified in the related
representation or warranty) as follows:

                  (i)  The Seller has been duly created and is validly existing
         and in good standing as a corporation under the laws of the State of
         Delaware;

                  (ii) The execution and delivery of this Agreement by the
         Seller and its performance of and compliance with the terms of this
         Agreement will not violate the Seller's charter or by-laws and will not
         conflict with or result in a breach of any of the terms or provisions
         of, or constitute a default under, any indenture, mortgage, deed of
         trust, loan


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         agreement or other material agreement or instrument to which the Seller
         is a party or by which the Seller or to which any of the property or
         assets of the Seller is subject;

                  (iii) The Seller has all requisite corporate power, authority
         and capacity to enter into this Agreement and to perform the
         obligations required of it hereunder. This Agreement, assuming due
         authorization, execution and delivery by the Purchaser, constitutes a
         valid and legally binding obligation of the Seller, enforceable against
         the Seller in accordance with its terms, subject, as to enforcement, to
         bankruptcy, insolvency, reorganization and other similar laws of
         general applicability relating to or affecting creditors' rights and to
         general equity principles, regardless of whether such enforcement is
         considered in a proceeding in equity or at law. No consent, approval,
         authorization or order of or registration with, or notice to, any
         governmental authority or court is required, under state or federal law
         prior to the execution, delivery, performance of or compliance by the
         Seller with this Agreement or the consummation by the Seller with any
         other transaction contemplated hereby;

                  (iv) The Seller is not in default with respect to any order or
         decree of any court or any order, regulation or demand of any federal,
         state, municipal or governmental agency, which default might have
         consequences that would materially and adversely affect the condition
         (financial or other) or operations of the Seller or its properties or
         might have consequences that would affect its performance hereunder;

                  (v) No litigation is pending or, to the best of the Seller's
         knowledge, threatened against the Seller which would prohibit its
         entering into this Agreement or performing its obligations under this
         Agreement;

                  (vi) The subservicers servicing on behalf of the seller are
         approved conventional servicers for FNMA or FHLMC in good standing;

                  (vii) The consummation of the transactions contemplated by
         this Agreement are in the ordinary course of business of the Seller,
         and the transfer, assignment and conveyance of the Mortgage Notes and
         the Mortgages by the Seller pursuant to this Agreement is not subject
         to the bulk transfer or any similar statutory provisions in effect in
         the State of Michigan;

                  (viii)   With respect to each Mortgage Loan:

                           1) that the information set forth in the Mortgage
                  Loan Schedule appearing as an exhibit to this Agreement is
                  true and correct in all material respects at the date or dates
                  respecting which such information is furnished as specified
                  therein;



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                           2) the Seller is the sole owner and holder of each
                  Mortgage Loan free and clear of all liens, pledges, charges or
                  security interests of any nature and has full right and
                  authority, subject to no interest or participation of, or
                  agreement with, any other party, to sell and assign the same
                  and, upon the Seller's receipt of the Purchase Price, the
                  Purchaser shall own and hold such Mortgage Loan free and clear
                  of all liens, pledges, charges or security interests of any
                  nature;

                           3) no payment of principal of or interest on or in
                  respect of any Mortgage Loan is 30 days or more past due from
                  the Due Date of such payment;

                           4) to the best of the Seller's knowledge, as of the
                  date of the transfer of the Mortgage Loans to the Purchaser,
                  there is no valid offset, defense or counterclaim to any
                  Mortgage Note or Mortgage;

                           5) there is no proceeding pending, or to the best of
                  the Seller's knowledge, threatened for the total or partial
                  condemnation of any of the real property, together with any
                  improvements thereto, securing the indebtedness of the
                  Mortgagor under the related Mortgage Loan (the "Mortgaged
                  Property") and the Mortgaged Property is free of material
                  damage and is in good repair and neither the Mortgaged
                  Property nor any improvement located on or being part of the
                  Mortgaged Property is in violation of any applicable zoning
                  law or regulation;

                           6) that each Mortgage Loan complies in all material
                  respects with applicable state or federal laws, regulations
                  and other requirements, pertaining to usury, equal credit
                  opportunity, disclosure laws and all applicable anti-predatory
                  laws, and each Mortgage Loan was not usurious at the time of
                  origination;

                           7) to the best of the Seller's knowledge, all
                  insurance premiums, water, sewer and municipal charges,
                  leasehold payments and ground rents previously due and owing
                  with respect to each Mortgaged Property have been paid and all
                  taxes and governmental assessments previously due and owing,
                  and which may become a lien against the Mortgaged Property,
                  with respect to the Mortgaged Property have been paid;

                           8) that each Mortgage Note and the related Mortgage
                  are genuine and each is the legal, valid and binding
                  obligation of the maker thereof, enforceable in accordance
                  with its terms except as such enforcement may be limited by
                  bankruptcy, insolvency, reorganization or other similar laws
                  affecting the enforcement of creditors' rights generally and
                  by general equity principles (regardless of whether such
                  enforcement is considered in a proceeding in equity or at
                  law); all parties to the Mortgage Note and the Mortgage had
                  legal capacity to execute the Mortgage Note and the Mortgage;
                  and each Mortgage Note and Mortgage have been duly and
                  properly executed by the Mortgagor;


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                           9) that each Mortgage is a valid and enforceable
                  perfected first lien on the property securing the related
                  Mortgage Note, and that each Mortgage Loan is covered by an
                  ALTA mortgagee title insurance policy or other form of policy
                  or insurance acceptable to FNMA or FHLMC, issued by, and is a
                  valid and binding obligation of, a title insurer acceptable to
                  FNMA or FHLMC insuring the originator, its successor and
                  assigns, as to the lien of the Mortgage in the original
                  principal amount of the Mortgage Loan subject only to (a) the
                  lien of current real property taxes and assessments not yet
                  due and payable, (b) covenants, conditions and restrictions,
                  rights of way, easements and other matters of public record as
                  of the date of recording of such Mortgage acceptable to
                  mortgage lending institutions in the area in which the
                  Mortgaged Property is located or specifically referred to in
                  the appraisal performed in connection with the origination of
                  the related Mortgage Loan and (c) such other matters to which
                  like properties are commonly subject which do not
                  individually, or in the aggregate, materially interfere with
                  the benefits of the security intended to be provided by the
                  Mortgage;

                           10) neither the Seller nor any prior holder of any
                  Mortgage or Mortgage Note has, except as the Mortgage File may
                  reflect, impaired, waived, altered or modified the Mortgage or
                  Mortgage Note in any respect, except by a written instrument
                  which has been recorded, if necessary to protect the interests
                  of the Purchaser and which has been delivered to the
                  Purchaser. The substance of any such waiver, alteration or
                  modification has been approved by the issuer of any primary
                  mortgage insurance policy covering the Mortgage Loan and title
                  insurer, to the extent required by the policies, and its terms
                  are reflected in the Mortgage Loan Schedule. No Mortgage has
                  been satisfied, cancelled or subordinated in whole or in part;
                  No Mortgaged Property has been released in whole or in part
                  from the lien of the Mortgage; No instrument of release,
                  cancellation, modification or satisfaction has been executed
                  with respect to the Mortgage Loan;

                           11) that each Mortgaged Property consists of a fee
                  simple estate or condominium form of ownership in real
                  property;

                           12) the condominium projects that include the
                  condominiums that are the subject of any condominium loan are
                  acceptable to FNMA or FHLMC;

                           13) no foreclosure action is threatened or has been
                  commenced with respect to the Mortgage Loan; and except for
                  payment delinquencies not in excess of 30 days, there is no
                  default, breach, violation or event of acceleration existing
                  under the Mortgage or the related Mortgage Note and, to the
                  best of the Seller's knowledge, no event which, with the
                  passage of time or with notice and the expiration of any grace
                  or cure period, would constitute a default, breach, violation
                  or event of acceleration; and the Seller has not waived any
                  default, breach, violation or event of acceleration;


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                           14) that each Mortgage Loan was originated on FNMA or
                  FHLMC uniform instruments for the state in which the Mortgaged
                  Property is located;

                           15) that based upon a representation by each
                  Mortgagor at the time of origination or assumption of the
                  applicable Mortgage Loan, approximately 93.95% of the Mortgage
                  Loans measured by principal balance were to be secured by
                  owner-occupied residences and approximately 6.05% of the
                  Mortgage Loans measured by principal balance were secured by
                  owner-occupied second home residences;

                           16) that an appraisal of each Mortgaged Property was
                  conducted at the time of origination of the related Mortgage
                  Loan, and that each such appraisal was conducted in accordance
                  with FNMA or FHLMC criteria, on FNMA or FHLMC forms and
                  comparables on at least three properties were obtained;

                           17) that no Mortgage Loan had a Loan-to-Value Ratio
                  at origination in excess of 95.00%;

                           18) the Mortgage Loans were not selected in a manner
                  to adversely affect the interests of the Purchaser and the
                  Seller knows of no conditions which reasonably would cause it
                  to expect any Mortgage Loan to become delinquent or otherwise
                  lose value;

                           19) each Mortgage Loan was either (A) originated
                  directly by or closed in the name of either: (i) a savings and
                  loan association, savings bank, commercial bank, credit union,
                  insurance company, or similar institution which is supervised
                  and examined by a federal or state authority or (ii) a
                  mortgagee approved by the Secretary of Housing and Urban
                  Development pursuant to Sections 203 and 211 of the National
                  Housing Act or (B) originated or underwritten by an entity
                  employing underwriting standards consistent with the
                  underwriting standards of an institution as described in
                  subclause (A)(i) or (A)(ii) above;

                           20) each Mortgage Loan is a "qualified mortgage"
                  within the meaning of Section 860G of the Internal Revenue
                  Code of 1986, without regard to Section 1.860 G-2(f) of the
                  REMIC provisions or any similar rule;

                           21) that no Mortgage Loan permits negative
                  amortization or the deferral of accrued interest;

                           22) pursuant to the terms of the applicable Mortgage,
                  all buildings or other improvements upon each Mortgaged
                  Property are insured by an insurer acceptable to FNMA or FHLMC
                  against loss by fire, hazards of extended coverage and such
                  other hazards as are customary in the area where the Mortgaged
                  Property is located


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                  pursuant to insurance policies conforming to the requirements
                  of FNMA or FHLMC. If upon origination of any Mortgage Loan,
                  the Mortgaged Property was in an area identified in the
                  Federal Register by the Federal Emergency Management Agency as
                  having special flood hazards (and such flood insurance has
                  been made available) a flood insurance policy meeting the
                  requirements of the current guidelines of the Federal
                  Insurance Administration is in effect which policy conforms to
                  the requirements of FNMA or FHLMC. All individual insurance
                  policies contain a standard mortgagee clause naming the Seller
                  and its successors and assigns as mortgagee, and all premiums
                  thereon have been paid. Each Mortgage obligates the Mortgagor
                  thereunder to maintain the hazard insurance policy at the
                  Mortgagor's cost and expense, and on the Mortgagor's failure
                  to do so, authorizes the holder of the Mortgage to obtain and
                  maintain such insurance at such Mortgagor's cost and expense,
                  and to seek reimbursement therefor from the Mortgagor. Where
                  required by state law or regulation, the Mortgagors have been
                  given an opportunity to choose the carrier of the required
                  hazard insurance policy, provided the policy is not a "master"
                  or "blanket" hazard insurance policy covering the common
                  facilities of a planned unit development. The hazard insurance
                  policy is the valid and binding obligation of the insurer, is
                  in full force and effect, and will be in full force and effect
                  and inure to the benefit of the Purchaser upon the
                  consummation of the transactions contemplated by this
                  Agreement. Seller has not engaged in, and has no knowledge of
                  the Mortgagor's or any subservicer s having engaged in, any
                  act or omission which would impair the coverage of any such
                  policy, the benefits of the endorsement provided for herein,
                  or the validity and binding effect of either, including,
                  without limitation, no unlawful fee, commission, kickback or
                  other unlawful compensation or value of any kind has been or
                  will be received, retained or realized by any attorney, firm
                  or other person or entity, and no such unlawful items have
                  been received, retained or realized by the Seller. All flood
                  insurance and hazard insurance premiums have been paid when
                  due;

                           23) each Mortgage Loan has been closed and the
                  proceeds of the Mortgage Loan have been fully disbursed and
                  there is no requirement for future advances thereunder, and
                  any and all requirements as to completion of any on-site or
                  off -site improvement included in the appraised value thereof,
                  and as to disbursements of any escrow funds therefor have been
                  complied with. All costs, fees and expenses incurred in making
                  or closing each Mortgage Loan and the recording of the related
                  Mortgage were paid, and the applicable Mortgagor is not
                  entitled to any refund of any amounts paid or due under the
                  Mortgage Note or Mortgage;

                           24) with respect to each Mortgage Loan with a
                  Loan-to-Value Ratio greater than 80%, the excess of the
                  principal balance of such Mortgage Loan to the percentage of
                  the appraised value thereof specified by FNMA is and will be
                  insured as to payment defaults by a primary mortgage insurance
                  policy issued by an insurer, and in a form, acceptable to FNMA
                  or FHLMC. All provisions of such primary mortgage insurance
                  policy have been and are being complied with, such policy is
                  in


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                  full force and effect, and all premiums due thereunder have
                  been paid. No action, inaction or event has occurred and no
                  state of facts exists that has, or will result in the
                  exclusion from, denial of, or defense to coverage. Any
                  Mortgage Loan subject to a primary mortgage insurance policy
                  obligates the Mortgagor thereunder to maintain the primary
                  mortgage insurance policy and to pay all premiums and charges
                  in connection therewith. The mortgage interest rate for the
                  Mortgage Loan as set forth on the Mortgage Loan Schedule is
                  net of any such insurance premium;

                           25) to the best of the Seller's knowledge each
                  Mortgaged Property is free from any and all toxic or hazardous
                  substances and there exists no violation of any local, state
                  or federal environmental law, rule or regulation;

                           26) all inspections, licenses and certificates
                  required to be made or issued with respect to all occupied
                  portions of each Mortgaged Property and, with respect to the
                  use and occupancy of the same, including, but not limited to,
                  certificates of occupancy and fire underwriting certificates,
                  have been made or obtained from the appropriate authorities;

                           27) each Mortgage Loan has been properly serviced in
                  accordance with all applicable federal, state and local laws,
                  the terms of the Mortgage, Mortgage Note and related Mortgage
                  Loan documents and all applicable guidelines to any prior
                  mortgagee. With respect to escrow deposits and escrow
                  payments, all such payments are in the possession of the
                  Seller and there exist no deficiencies in connection therewith
                  for which customary arrangements for repayment thereof have
                  not been made. All escrow payments have been collected in full
                  compliance with state and federal law. An escrow of funds is
                  not prohibited by applicable law and has been established in
                  accordance with law, and by Servicer's best estimate in an
                  amount sufficient to pay for every item which remains unpaid
                  and which has been assessed but is not yet due and payable. No
                  escrow deposits or escrow payments or other charges or
                  payments due the Seller have been capitalized under any
                  Mortgage or any Mortgage Note. Any interest required to be
                  paid pursuant to state and local law has been properly paid
                  and credited;

                           28) as of the Closing Date, each Mortgage Loan will
                  have a transferable life-of-loan tax service contract with
                  First American Real Estate Tax Service or another tax service,
                  provided that such tax service is acceptable to the Purchaser;

                           29) Each Mortgage Note and Assignment of Mortgage has
                  been, or will be, delivered to the Purchaser or its custodian
                  for each Mortgage Loan;

                           30) the Mortgage Loan was underwritten in accordance
                  with the Seller's underwriting standards in effect at the time
                  the Mortgage Loan was originated;



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                           31) no fraud occurred on the part of the Seller, the
                  Mortgagor or, to the best of the Seller's knowledge, any third
                  party in connection with the origination of the Mortgage Loan;

                           32) each Mortgage Loan that has a Loan-to-Value Ratio
                  at origination in excess of 80% is covered by a primary
                  mortgage insurance policy;

                           33) no Loan is a "high-cost home loan" as defined in
                  the Georgia Fair Lending Act, as amended, or in the New York
                  Predatory Lending Law, codified as N.Y. Banking Law Section
                  6-l, N.Y. Gen. Bus. Law Section 771-a, and N.Y. Real Prop.
                  Acts Law Section 1302, the Arkansas Home Loan Protection Act,
                  as amended, the Kentucky Revised Statutes Section 360.100, as
                  amended, or the Florida Home Loan Protection Act ss.494.007
                  (the "Florida Act"); no Loan is a "covered loan" as defined in
                  the District of Columbia Home Loan Protection Act
                  ss.26-1151.01 (the "D.C. Act"); no Loan is a "high-rate,
                  high-fee mortgage" as defined in Maine Consumer Credit Code --
                  Truth In Lending ss.8-103 (the "Maine Act"); and no Loan is a
                  "home loan" as defined in Nevada Revised Statutes title 52, as
                  amended by Assembly Bill No. 284, 72nd Session (Nevada 2003)
                  (the "Nevada Act"); and

                           34) none of the Mortgage Loans are subject to the
                  Home Ownership and Equity Protection Act of 1994 or any
                  comparable state law.

         It is understood and agreed that the representations and warranties set
forth in this SECTION 8 shall survive the sale of the Mortgage Loans to the
Purchaser and shall inure to the benefit of the Purchaser, notwithstanding any
restrictive or qualified endorsement on any Mortgage Note (or lost note
affidavit and indemnity) or assignment of Mortgage or the examination of any
Mortgage File.

         Upon discovery by either the Seller, the Purchaser or its designees of
a breach of any of the foregoing representations or warranties of the Seller
which materially and adversely affects (1) the value of any of the Mortgage
Loans actually delivered or (2) the interests of the Purchaser therein, the
party discovering such breach shall give prompt written notice to the other.
Within 90 (ninety) days of its discovery or its receipt of notice of any such
breach of a representation or warranty, the Seller shall, with respect to the
Mortgage Loan(s) to which such breach relates, either (i) cure such breach in
all material respects (except for a breach of that portion of the representation
and warranty relating to any casualty from the presence of hazardous waste or
hazardous substances), (ii) repurchase such Mortgage Loan or Mortgage Loans (or
any property acquired in respect thereof) from the Purchaser at the Purchase
Price, as adjusted for the then current principal balance or (iii) within the 90
(ninety)-day period following the Closing Date substitute another mortgage loan
for such Mortgage Loan. Such substitute mortgage loan shall on the date of
substitution, (a) have a principal balance not in excess of the principal
balance of the defective Mortgage Loan, (b) be accruing interest at a rate of
interest at least equal to that of the defective Mortgage Loan, (c) have a
remaining term to stated maturity not greater than, and not more than two years
less than, that of the Mortgage Loan so substituted, (d) have an original
loan-to-value ratio not higher than that of the Mortgage Loan so substituted and
a current loan-to-value ratio not higher than that of the Mortgage


                                      -11-

<PAGE>



Loan so substituted, and (e) comply with all the representations and warranties
relating to Mortgage Loans set forth herein, as of the date of substitution
(such mortgage loan being referred to herein as a "QUALIFYING SUBSTITUTE
MORTGAGE LOAN"). If the breach of representation and warranty that gave rise to
the obligation to repurchase or substitute a Loan pursuant to this SECTION 8 was
the representation set forth in clause (viii)(6) of this SECTION 8, then the
Seller shall pay to the Trust Fund, concurrently with and in addition to the
remedies provided in the preceding sentence, an amount equal to any liability,
penalty or reasonable expense that was actually incurred and paid out of or on
behalf of the Trust Fund, and that directly resulted from such breach, or if
incurred and paid by the Trust Fund thereafter, concurrently with such payment.
Except as set forth in SECTION 12 hereof, it is understood and agreed that the
obligations of the Seller set forth in this SECTION 8 to cure, substitute for or
repurchase a defective Mortgage Loan constitute the sole remedies of the
Purchaser respecting a breach of the foregoing representations and warranties.

         The Purchaser, upon receipt by it of the full amount of the Purchase
Price as adjusted for the then current principal balance for a Mortgage Loan
that is repurchased, or upon receipt of the Mortgage File for a Qualifying
Substitute Mortgage Loan for a Mortgage Loan that is substituted or repurchased,
shall release or cause to be released and reassign to the Seller the related
Mortgage File for the Mortgage Loan that is substituted and shall execute and
deliver such instruments of transfer or assignment, in each case without
recourse, representation, or warranty, as shall be necessary to vest in the
Seller or its designee or assignee title to any such substituted Mortgage Loan
released pursuant hereto, free and clear of all security interests, liens and
other encumbrances created by this Agreement, which instruments shall be
prepared by the Seller at its expense and shall be reasonably acceptable to the
Purchaser, and the Purchaser shall have no further responsibility with respect
to the Mortgage File relating to such Mortgage Loan that is substituted.

         Any cause of action against the Seller or relating to or arising out of
the breach of any representations and warranties made in this SECTION 8 shall
accrue as to any Mortgage Loan upon (i) discovery of such breach by the
Purchaser or notice thereof by the Seller to the Purchaser, (ii) failure by the
Seller to cure such breach, repurchase such Mortgage Loan or substitute a
Qualifying Substitute Mortgage Loan as specified above, and (iii) demand upon
the Seller by the Purchaser for all amounts payable in respect of such Mortgage
Loan.

SECTION 9.   REPRESENTATIONS, WARRANTIES AND AGREEMENTS OF PURCHASER.

         (a) The Purchaser hereby represents and warrants to the Seller, as of
the date hereof (or such other date as is specified in the related
representation or warranty) as follows:

                  (i) The Purchaser is a corporation duly formed and validly
         existing under the laws of the State of Delaware;

                  (ii) The execution and delivery of this Agreement by the
         Purchaser and its performance of and compliance with the terms of this
         Agreement will not violate the Purchaser's corporate charter or by-laws
         or will not conflict with or result in a breach of any


                                     -12-

<PAGE>



         of the terms or provisions of, or constitute a default under, any
         indenture, mortgage, deed of trust, loan agreement or other material
         agreement or instrument to which the Purchaser is a party or by which
         the Purchaser or to which any property or assets of the Purchaser is
         subject;

                  (iii) The Purchaser has all requisite corporate power,
         authority and capacity to enter into this Agreement and to perform the
         obligations required of it hereunder. This Agreement, assuming due
         authorization, execution and delivery by the Seller, constitutes a
         valid and legally binding obligation of the Purchaser, enforceable
         against the Purchaser in accordance with its terms, subject, as to
         enforcement, to bankruptcy, insolvency, reorganization and other
         similar laws of general applicability relating to or affecting
         creditors' rights and to general equity principles, regardless of
         whether such enforcement is considered in a proceeding in equity or at
         law. No consent, approval, authorization or order of or registration
         with, or notice to, any governmental authority or court is required,
         under state or federal law prior to the execution, delivery,
         performance of or compliance by the Purchaser with this Agreement or
         the consummation by the Purchaser with any other transaction
         contemplated hereby;

                  (iv) The Purchaser is not in default with respect to any order
         or decree of any court or any order, regulation or demand of any
         federal, state, municipal or governmental agency, which the Purchaser
         default might have consequences that would materially and adversely
         affect the condition (financial or other) or operations of the
         Purchaser or its properties or might have consequences that would
         affect its performance hereunder; and

                  (v) No litigation is pending or, to the best of the
         Purchaser's knowledge, threatened against the Purchaser which would
         prohibit its entering into this Agreement or performing its obligations
         under this Agreement;

SECTION 10.  PURCHASER'S CONDITIONS TO CLOSING. The obligations of the Purchaser
under this Agreement shall be subject to the satisfaction, on or prior to the
Closing Date, of the following conditions:

         (a) The obligations of the Seller required to be performed by it on or
prior to the Closing Date pursuant to the terms of this Agreement shall have
been duly performed and complied with and all of the representations and
warranties of the Seller under this Agreement shall be true and correct as of
the date hereof and as of the Closing Date, and no event shall have occurred
which, with notice or the passage of time, or both, would constitute a default
under this Agreement, and the Purchaser shall have received a certificate to
that effect signed by an Authorized Officer (as defined below) of the Seller.

         (b) The Purchaser or the Purchaser's document custodian shall have
received, or the Purchaser's attorney shall have received in escrow, all of the
following closing documents, in such forms as are agreed upon and acceptable to
the Purchaser, duly executed by all signatories other than the Purchaser, as
required pursuant to the respective terms thereof:


                                      -13-

<PAGE>




                  (i) An assignment or assignments of the Mortgage Loans to the
         Purchaser substantially in the form attached hereto as EXHIBIT B with
         such changes as are required to adapt the assignment to the proper form
         in the jurisdiction where the related Mortgage Property is located, and
         each original Mortgage Note (or lost note affidavit and indemnity),
         duly endorsed originally or by facsimile, without recourse, to the
         Purchaser, in each case in accordance with the instructions set forth
         in EXHIBIT A attached hereto, which assignment or assignments and
         Mortgage Note (or lost note affidavit and indemnity) shall be delivered
         to and held by the Purchaser or its agent on behalf of the Purchaser;

                  (ii) The Mortgage Loan Schedule prepared by Seller dated as of
         the related Closing Date and attached hereto;

                  (iii) A certificate signed by an officer, which officer may be
         either a senior vice president, a vice president, an assistant vice
         president or assistant secretary (an "AUTHORIZED OFFICER"), dated as of
         the Closing Date, substantially in the form attached hereto as EXHIBIT
         C, to the parties hereto, and attached thereto copies of the charter
         and by-laws and a Good Standing Certificate or a memorandum setting
         forth the verbal assurances from the appropriate regulatory authorities
         with respect to the Seller will be immediately forthcoming; and

                  (iv) An opinion of Seller's counsel in substantially the form
         attached hereto as EXHIBIT D.

         (c) The Seller will furnish to the Purchaser such other certificates of
its officers or others and such other documents to evidence fulfillment of the
conditions set forth in this Agreement as the Purchaser and its attorney may
reasonably request.

SECTION 11.  SELLER'S CONDITIONS TO CLOSING.

         The obligations of the Seller under this Agreement shall be subject to
the satisfaction, on or prior to the Closing Date, of the following conditions:

         (a) The obligations of the Purchaser required to be performed by it on
or prior to the Closing Date pursuant to the terms of this Agreement shall have
been duly performed and complied with and all of the representations and
warranties of the Purchaser under this Agreement shall be true and correct as of
the date hereof and as of the Closing Date, and no event shall have occurred
which, with notice or the passage of time, or both, would constitute a default
under this Agreement, and the Seller shall have received a certificate to that
effect signed by an Authorized Officer of the Purchaser;

         (b) The Seller shall have received, or the Seller's attorney shall have
received in escrow, a certificate signed by an Authorized Officer of the
Purchaser dated as of the Closing Date, in the


                                      -14-

<PAGE>



form acceptable to the parties hereto, and attached thereto the resolutions of
the Purchaser authorizing the transactions contemplated by this Agreement,
together with copies of the Articles of Association and by-laws as of a recent
date with respect to the Purchaser; and

         (c) The Purchaser will furnish to the Seller such other certificates of
its officers or others and such other documents to evidence fulfillment of the
conditions set forth in this Agreement as the Seller and its attorney may
reasonably request.

SECTION 12.  NOTICES.

         All demands, notices and communications hereunder shall be in writing
and shall be deemed to have been duly given if mailed, by registered or
certified mail, return receipt requested, or, if by other means, when received
by the other party. Notices to the Seller shall be directed to Washington Mutual
Mortgage Securities Corp., 1201 Third Avenue, WMT 1706, Seattle, Washington
98101, Attention: Legal Department; and notices to the Purchaser shall be
directed to ABN AMRO Mortgage Corporation, 135 South LaSalle Street, Suite 925,
Chicago, Illinois 60603, Attention: Maria Fregosi - First Vice President - ABN
AMRO Mortgage Operations, with a copy to LaSalle Bank Corporation, 135 South
LaSalle Street, Chicago, Illinois 60603, Attention: Marlene Ellis - Assistant
Counsel; or such other addresses as may hereafter be furnished to the other
party by like notice.

SECTION 13.  TERMINATION.

         This Agreement may be terminated (a) by the mutual consent of the
parties hereto, or (b) by the Purchaser if the conditions to the Purchaser's
obligations to closing set forth under SECTION 10 hereof are not fulfilled as
and when required to be fulfilled or (c) by the Seller if the Purchaser's
obligations under SECTION 11 hereof are not fulfilled as and when required. In
the event of a termination pursuant to SECTION 13(B), the Seller agrees that it
will pay the out-of-pocket fees and expenses of the Purchaser in connection with
the transactions contemplated by this Agreement and in the event of a
termination pursuant to SECTION 13(C), the Purchaser agrees that it will pay the
out- of-pocket fees and expenses of the Seller in connection with the
transactions contemplated by this Agreement.

SECTION 14.  REPRESENTATIONS, WARRANTIES AND AGREEMENTS TO SURVIVE DELIVERY.

         All representations, warranties and agreements contained in this
Agreement, or in certificates of officers of the Seller and the Purchaser
submitted pursuant hereto, shall remain operative and in full force and effect
and shall survive transfer and sale of the Mortgage Loans to the Purchaser.



                                      -15-

<PAGE>



SECTION 15.  SEVERABILITY.

         If any provision of this Agreement shall be prohibited or invalid under
applicable law, the Agreement shall be ineffective only to such extent, without
invalidating the remainder of this Agreement.

SECTION 16.  COUNTERPARTS.

         This Agreement may be executed in any number of counterparts, each of
which shall be an original, but both of which together shall constitute one and
the same agreement.

SECTION 17.  GOVERNING LAW.

         This Agreement shall be deemed to have been made in the State of New
York and shall be interpreted in accordance with the laws of such state without
regard to the principles of conflicts of law of such state.

SECTION 18.  FURTHER ASSURANCES.

         The Seller and the Purchaser agree to execute and deliver such
instruments and take such actions as the other party may, from time to time,
reasonably request in order to effectuate the purpose and to carry out the terms
of this Agreement.

SECTION 19.  SUCCESSORS AND ASSIGNS.

         This Agreement shall be binding upon and inure to the benefit of and be
enforceable by the Seller and the Purchaser and their permitted successors and
assigns. The Seller acknowledges and agrees that the Purchaser may assign its
rights under this Agreement. Any person into which the Seller may be merged or
consolidated (or any person resulting from any merger or consolidation involving
the Seller), or any person succeeding to the business of the Seller shall be
considered the "successor" of the Seller hereunder. Except as provided in the
two preceding sentences, this Agreement cannot be assigned, pledged or
hypothecated by any party hereto without the written consent of the other party
to this Agreement. Notwithstanding anything to the contrary in this SECTION 19,
the parties hereto agree that the Purchaser has the right to assign its rights
and interest in, to and under SECTION 8 hereof.

SECTION 20.  AMENDMENTS.

         No term or provision of this Agreement may be waived or modified unless
such waiver or modification is in writing and signed by a duly authorized
officer of the party against whom such waiver or modification is sought to be
enforced.




                                      -16-

<PAGE>



         IN WITNESS WHEREOF, the Seller and the Purchaser have caused their
names to be signed hereto by their respective duly authorized officers as of the
date first above written.

                                    Washington Mutual Mortgage Securities Corp.,
                                    as Seller


                                    By:   /s/ Thomas G. Lehmann
                                        ----------------------------------------
                                    Name:     Thomas G. Lehmann
                                    Title:    First Vice President














                                           WAMU MORTGAGE LOAN PURCHASE AGREEMENT

<PAGE>



                                    ABN AMRO Mortgage Corporation,
                                    as Purchaser


                                    By:  /s/ Daniel J. Fischer
                                        ----------------------------------------
                                    Name:    Daniel J. Fischer
                                    Title:   Vice President














                                           WAMU MORTGAGE LOAN PURCHASE AGREEMENT

<PAGE>



                                   SCHEDULE 1

                             MORTGAGE LOAN SCHEDULE
                             ----------------------
                             (Provided upon request)







<PAGE>



                                   SCHEDULE 2

                       MORTGAGE LOAN SCHEDULE INFORMATION
                       ----------------------------------

         Each Mortgage Loan shall be identified by at least the following
details, among others, relating to each Mortgage Loan:

         (i)      the loan number of the Mortgage Loan;

         (ii)     the city, state and zip code of the Mortgaged Property;

         (iii)    the mortgage interest rate as of the Cut-Off Date;

         (iv)     the original term and maturity date of the related Mortgage
                  Note;

         (v)      the original principal balance;

         (vi)     the first payment date;

         (vii)    the monthly payment in effect as of the Cut-Off Date;

         (viii)   the date of the last paid installment of interest;

         (ix)     the unpaid principal balance as of the close of business on
                  the Cut-Off Date;

         (x)      the loan-to-value ratio at origination;

         (xi)     the type of property;

         (xii)    whether a primary mortgage insurance policy is in effect as of
                  the Cut-Off Date;

         (xiii)   the nature of occupancy at origination;

         (xiv)    the servicing fee;

         (xv)     the county in which the Mortgaged Property is located, if
                  available; and

         (xvi)    the closing date.



<PAGE>



                                   SCHEDULE 3

                            MORTGAGE FILE INFORMATION
                            -------------------------


         Each Mortgage File shall include at least the following documents,
among others, with respect to each Mortgage Loan transferred and assigned from
the Seller to the Purchaser, or its agent:

         (i)      the original Mortgage Note (or, if the original Mortgage Note
                  has been lost or destroyed, a lost note affidavit and
                  indemnity) bearing all intervening endorsements endorsed, "Pay
                  to the order of U.S. Bank National Association for the benefit
                  of the Certificateholders of ABN AMRO Mortgage Corporation
                  Series 2003-13 Attn: Corporate Trust Department, 2 Avenue de
                  Lafayette, Boston, MA 02111-1724, without recourse" and signed
                  in the name of the mortgagee at the request of the Seller by
                  an Authorized Officer showing an unbroken chain of title from
                  the originator thereof to the person endorsing;

         (ii)     (a) the original Mortgage with evidence of recording thereon,
                  and if the Mortgage was executed pursuant to a power of
                  attorney, a certified true copy of the power of attorney
                  certified by the recorder's office, with evidence of recording
                  thereon, or certified by a title insurance company or escrow
                  company to be a true copy thereof; PROVIDED, that if such
                  original Mortgage or power of attorney cannot be delivered
                  with evidence of recording thereon on or prior to the Closing
                  Date because of a delay caused by the public recording office
                  where such original Mortgage has been delivered for
                  recordation or because such original Mortgage has been lost,
                  the Seller shall deliver or cause to be delivered to the
                  Purchaser (with a copy to the Trustee (as defined in the
                  Pooling and Servicing Agreement)) a true and correct copy of
                  such Mortgage, together with (1) in the case of a delay caused
                  by the public recording office, a certificate signed by an
                  Authorized Officer of the Seller stating that such original
                  Mortgage has been dispatched to the appropriate public
                  recording official for recordation or (2) in the case of an
                  original Mortgage that has been lost, a certificate by the
                  appropriate county recording office where such Mortgage is
                  recorded or from a title insurance company or escrow company
                  indicating that such original was lost and the copy of the
                  original mortgage is a true and correct copy;

                  (b) the original assignment to "U.S. Bank National
                  Association, as Trustee," which assignment shall be in form
                  and substance acceptable for recording, or a copy certified
                  by the Seller as a true and correct copy of the original
                  assignment which has been sent for recordation. Subject to
                  the foregoing, such assignments may, if permitted by law, be
                  by blanket assignments for Mortgage Loans covering Mortgaged
                  Properties situated within the same county. If the assignment
                  is in blanket form, a copy of the assignment shall be
                  included in the related individual Mortgage File;





<PAGE>



         (iii)    the originals of any and all instruments that modify the terms
                  and conditions of the Mortgage Note, including but not limited
                  to modification, consolidation, extension and assumption
                  agreements including any adjustable rate mortgage (ARM) rider,
                  if any;

         (iv)     the originals of all required intervening assignments, if any,
                  with evidence of recording thereon, and if such assignment was
                  executed pursuant to a power of attorney, a certified true
                  copy of the power of attorney certified by the recorder's
                  office, with evidence of recording thereon, or certified by a
                  title insurance company or escrow company to be a true copy
                  thereof; PROVIDED, that if such original assignment or power
                  of attorney cannot be delivered with evidence of recording
                  thereon on or prior to the Closing Date because of a delay
                  caused by the public recording office where such original
                  assignment has been delivered for recordation or because such
                  original assignment has been lost, the Seller shall deliver or
                  cause to be delivered to the Purchaser (with a copy to the
                  Trustee (as defined in the Pooling and Servicing Agreement)) a
                  true and correct copy of such assignment, together with (a) in
                  the case of a delay caused by the public recording office, a
                  certificate signed by an Authorized Officer of the Seller
                  stating that such original assignment has been dispatched to
                  the appropriate public recording official for recordation or
                  (b) in the case of an original assignment that has been lost,
                  a certificate by the appropriate county recording office where
                  such assignment is recorded or from a title insurance company
                  or escrow company indicating that such original was lost and
                  the copy of the original assignment is a true and correct
                  copy;

         (v)      the original mortgagee policy of title insurance (including,
                  if applicable, the endorsement relating to the negative
                  amortization of the Mortgage Loans) or in the event such
                  original title policy is unavailable, any one of an original
                  title binder, an original preliminary title report or an
                  original title commitment or a copy thereof certified by the
                  title company with the original policy of title insurance to
                  follow within 180 days of the Closing Date;




                                       -2-

<PAGE>



                                    EXHIBIT A
                                    ---------

                               INSTRUCTION LETTER

                          ABN AMRO Mortgage Corporation
                       135 South LaSalle Street, Suite 925
                             Chicago, Illinois 60603


                                                               ________ __, 2003


Washington Mutual Mortgage Securities Corp.
75 North Fairway Drive
Vernon Hills, Illinois 60061

Dear Ladies and Gentlemen:

         Pursuant to the Mortgage Loan Purchase Agreement dated as of December
23, 2003 (the "PURCHASE AGREEMENT") between you and us, we have agreed to
purchase from you certain Mortgage Loans. All capitalized terms used herein and
not otherwise defined shall have the meanings set forth in the Purchase
Agreement.

         In order to facilitate these transactions, and for the purpose of
convenience only, we hereby authorize and direct you to:

Action                                                 Due Date
1.    Endorse mortgage notes (or lost note             one week prior to funding
      affidavits
      and indemnities) to:
      "Pay to the order of
      U.S. Bank National Association
      for the benefit of the Certificateholders
      of ABN AMRO Mortgage Corporation
      Series 2003-13, Attn: Corporate Trust
      Department, 2 Avenue de Lafayette,
      Boston, MA 02111-1724,
      without recourse"





2.    Assign mortgages to be recorded                  one week prior to funding
      to U.S. Bank National Association
      for the benefit of the Certificateholders
      of ABN AMRO Mortgage Corporation
      Series 2003-13:






<PAGE>



3.    Deliver to the Purchaser or its agent all        two business days after
      Mortgage Loan documents pertaining to each       funding
      loan

4.    Deliver to the Purchaser's servicer all          one week prior to
      Mortgage Loan servicing documents pertaining     Servicing transfer date
      to each loan


5.    Provide lost mortgage note affidavits,           one week prior to funding
      certified copies of all missing mortgages,
      and certified recorded copies of missing
      intervening assignments

6.    Mortgage Loan Schedule generated by              one day prior to funding
      Purchaser and agreed to by Seller


                                       Sincerely,

                                       ABN AMRO Mortgage Corporation


                                       By: _____________________________
                                       Name: ___________________________
                                       Title: __________________________




                                       -2-

<PAGE>



                                    EXHIBIT B
                                    ---------


                               FORM OF ASSIGNMENT


         Washington Mutual Mortgage Securities Corp., a Delaware corporation
(the "SELLER"), in exchange for $_______________ in hand paid and other good and
valuable consideration, hereby grants, bargains, sells, assigns, transfers,
conveys, and sets over to ABN AMRO Mortgage Corporation, a Delaware corporation
(the "PURCHASER"), all of the Seller's right, title, and interest in, to, and
under the mortgage loans listed on SCHEDULE 1 attached hereto, the mortgage
notes evidencing or relating to such mortgage loans, all mortgages, trust deeds,
title insurance policies, property insurance policies, chattel paper, loan
guaranties, loan accounts, surveys, instruments, certificates, and other
documents whatsoever evidencing or relating to such mortgage notes and mortgage
loans, and all books, ledgers, books of account, records, writings, data bases,
information, and computer software (and all documentation therefor or relating
thereto, and all licenses relating to or covering such computer software and/or
documentation), and all other property, rights, title, and interests whatsoever
relating to, used, or useful in connection with, or evidencing, embodying,
incorporating, or referring to, any of the foregoing (the "MORTGAGES"). The
Seller warrants to the Purchaser that the Seller is the owner of the Mortgages,
subject to no liens, claims, or encumbrances.





<PAGE>



Dated:  _____________, 2003          Washington Mutual Mortgage Securities Corp.


                                     By: _____________________________
                                       Name: _________________________
                                       Title: ________________________







                                       -2-

<PAGE>



ACKNOWLEDGED ON __________ __, 2003

ABN AMRO Mortgage Corporation


By: _____________________________
  Name: _________________________
  Title: ________________________











                                       -3-

<PAGE>



STATE OF    ____________   )
                           )
COUNTY OF   ____________   )


         I, ______________, a Notary Public in and for the said County and
State, do hereby certify that ____________, personally known to me to be the
same person whose name is subscribed to the foregoing instrument as
_______________ of __________________, appeared before me this day in person
and, being first sworn, acknowledged that he signed and delivered the said
instrument as his own free and voluntary act, and as the free and voluntary act
of said corporation as the ___________ of ____________, a ____________, for the
uses and purposes therein set forth and that he was duly authorized to execute
the said instrument by the __________________ of said
_________________.

         Given under my hand and seal, this ____ day of ____________, 2003.


                                      __________________________________
                                      Notary Public

                                      My commission expires:____________







                                       -4-

<PAGE>



                                    EXHIBIT C
                                    ---------

                          FORM OF OFFICER'S CERTIFICATE
                          -----------------------------





Dated as of the Closing Date

U.S. Bank National Association, as Trustee
225 Franklin Street, Boston, MA 02110
Attention: Corporate Trust, ABN AMRO 2003-13

RE:      ABN AMRO Mortgage Corporation
         Mortgage Pass-Through Certificates
         Series 2003-13

Ladies and Gentlemen:

All capitalized terms used but not defined herein shall have the meaning
ascribed to them in the Pooling and Servicing Agreement, dated as of December 1,
2003, among ABN AMRO Mortgage Corporation, as depositor, U.S. Bank National
Association, as trustee, and Washington Mutual Mortgage Securities Corp.
(WMMSC), as a seller and a servicer.

This is to advise you that the persons listed on the attached Schedule A are
Servicing Officers, as defined in Article I of such Pooling and Servicing
Agreement, and are authorized to take all actions and sign all documents as
indicated in the Pooling and Servicing Agreement. The signatures appearing
opposite the respective names of such Servicing Officers are their genuine
signatures. The list of Servicing Officers may be amended from time to time by
delivery to you of a revised schedule.

                                        Very truly yours,

                                        WASHINGTON MUTUAL MORTGAGE SECURITIES
                                        CORP.


                                        By: _____________________________
                                        Name:    Thomas G. Lehmann
                                        Title:   First Vice President





<PAGE>




                                  AMAC 2003-13
                        ASSISTANT SECRETARY'S CERTIFICATE

The undersigned, the duly elected Assistant Secretary of Washington Mutual
Mortgage Securities Corp., a Delaware corporation (the Company), hereby
certifies as follows.

         1. Attached hereto as EXHIBIT A is a true and correct copy of the
Amended Certificate of Incorporation of the Company, which is in full force and
effect on the date hereof.

         2. The Company has been duly incorporated and is validly existing as a
corporation in good standing under the laws of the State of Delaware.

         3. Attached hereto as EXHIBIT B is a true and correct copy of the By
laws of the Company which are in full force and effect on the date hereof.

         4. To the best of my knowledge, no proceedings looking toward
liquidation or dissolution of the Company are pending or contemplated.

         5. Attached hereto as EXHIBIT C are true and correct copies of
resolutions adopted by the Board of Directors of the Company, relating to the
authorization, execution and delivery of the Pooling and Servicing Agreement,
dated as of dated as of December 1, 2003, among ABN AMRO Mortgage Corporation,
as depositor, U.S. Bank National Association, as trustee, and Washington Mutual
Mortgage Securities Corp. (WMMSC), as a seller and a servicer (the Pooling and
Servicing Agreement and, together with the Purchase Agreement, the Agreements)
and (iii) each other agreement executed and delivered by the Company relating to
the above-referenced Series and the consummation of the transactions
contemplated by the foregoing agreements. Said resolutions have not been
amended, modified, annulled or revoked, and are in full force and effect as of
the date hereof, and the instruments referred to in said resolutions were
executed pursuant thereto and in compliance therewith.

         6. Attached hereto as EXHIBIT D is a true and correct copy of a
Certificate of Good Standing issued as of a recent date by the Secretary of
State of the State of Delaware with respect to the Company.

         7. Each person who, as an officer or representative of the Company,
signed any of the Agreements or any other agreement or document delivered by the
Company prior to or on the date hereof in connection with the transactions
contemplated by the foregoing agreements was at the time of such signing and
delivery and is as of the date hereof, duly elected or appointed, qualified and
acting as such officer, and the signatures of such persons appearing on such
documents are their genuine signatures.

         8. Capitalized terms used herein but not defined herein shall have the
meanings assigned to them in the Pooling and Servicing Agreement.



                                       -2-

<PAGE>



IN WITNESS WHEREOF, I have signed my name as of the Closing Date.


                                                 By:___________________________
                                                 Name:    Thomas G. Lehmann
                                                 Title:   Secretary





                                       -3-

<PAGE>


                    [OPINION TO BE REVISED IN ACCORDANCE WITH

                    GENERAL COUNSEL'S FORM OF OPINION LETTER]

                                    EXHIBIT D
                                    ---------

                      [OPINION OF SELLER'S IN-HOUSE COUNSEL

                         PURSUANT TO SECTION 10(B)(IV)]
                                     ------------------