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           FIRST UNION RESIDENTIAL SECURITIZATION TRANSACTIONS, INC.,

                                  as Purchaser,

                                       and

                           FIRST UNION NATIONAL BANK,

                                   as Seller,



                        MORTGAGE LOAN PURCHASE AGREEMENT

                          Dated as of February 1, 1999


                        FURST MORTGAGE LOAN TRUST 1999-A

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                                Table of Contents

<TABLE>
<CAPTION>
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                                                                                                               ----

<S>                                                                                                            <C>
ARTICLE I   DEFINITIONS...........................................................................................1
         Section 1.1 Definitions..................................................................................1

ARTICLE II  SALE OF MORTGAGE LOANS; PAYMENT OF PURCHASE PRICE.....................................................2
         Section 2.1 Sale of Mortgage Loans.......................................................................2
         Section 2.2 Reserved.....................................................................................2
         Section 2.3 Obligations of Seller Upon Sale..............................................................2
         Section 2.3 Payment of Purchase Price for the Mortgage Loans.............................................4

ARTICLE III  REPRESENTATIONS AND WARRANTIES; REMEDIES FOR BREACH..................................................5
         Section 3.1 Seller Representations and Warranties........................................................5
         Section 3.2 Seller Representations and Warranties Relating to the Mortgage Loans.........................6

ARTICLE IV  SELLER'S COVENANTS....................................................................................7
         Section 4.1 Covenants of the Seller......................................................................7

ARTICLE V  SERVICING..............................................................................................7
         Section 5.1 Servicing....................................................................................7

ARTICLE VI  INDEMNIFICATION WITH RESPECT TO THE MORTGAGE LOANS....................................................8
         Section 6.1 Indemnification..............................................................................8

ARTICLE VII TERMINATION..........................................................................................11
         Section 7.1 Termination.................................................................................11

ARTICLE VIII  MISCELLANEOUS PROVISIONS...........................................................................12
         Section 8.1 Amendment...................................................................................12
         Section 8.2 Governing Law...............................................................................12
         Section 8.3 Notices.....................................................................................12
         Section 8.4 Severability of Provisions..................................................................13
         Section 8.5 Counterparts................................................................................13
         Section 8.6 Further Agreements..........................................................................13
         Section 8.7 Intention of the Parties....................................................................13
         Section 8.8 Successors and Assigns: Assignment of Purchase Agreement....................................14
         Section 8.9 Survival....................................................................................14

         SCHEDULE I                 MORTGAGE LOANS
</TABLE>


<PAGE>   3

         MORTGAGE LOAN PURCHASE AGREEMENT (the "Purchase Agreement"), dated as
of February 1, 1999 between First Union National Bank (the "Seller") and First
Union Residential Securitization Transactions, Inc. (the "Purchaser").

                               W I T N E S S E T H

         WHEREAS, the Seller is the owner of the notes or other evidence of
indebtedness (the "Mortgage Notes") so indicated on Schedule I hereto referred
to below, and Related Documents (as defined in Section 2.3 hereof)
(collectively, the "Mortgage Loans"); and

         WHEREAS, the Seller, in the case of the Mortgage Loans, owns the
mortgages (the "Mortgages") on the properties (the "Mortgaged Properties")
securing such Mortgage Loans, including rights to (a) any property acquired by
foreclosure or deed in lieu of foreclosure or otherwise and (b) the proceeds of
any insurance policies covering the Mortgage Loans or the Mortgaged Properties
or the obligors on the Mortgage Loans;

         WHEREAS, the parties hereto desire that the Seller sell the Mortgage
Loans to the Purchaser pursuant to the terms of this Purchase Agreement; and

         WHEREAS, pursuant to the terms of a Pooling and Servicing Agreement
dated as of February 1, 1999 (the "Pooling and Servicing Agreement") among the
Purchaser, as depositor, the Seller, as seller, as master servicer (the "Master
Servicer") and as Trust Administrator, Norwest Bank Minnesota, National
Association, as document custodian and as trustee (the "Trustee"), the Purchaser
will convey the Mortgage Loans to FURST Mortgage Loan Trust 1999-A (the "Trust
Fund"); and

         NOW, THEREFORE, in consideration of the mutual covenants herein
contained, the parties hereto agree as follows:

                                    ARTICLE I

                                   DEFINITIONS

         SECTION 1.1 DEFINITIONS.

         All capitalized terms used but not defined herein shall have the
meanings assigned thereto in the Pooling and Servicing Agreement.



<PAGE>   4

                                   ARTICLE II

                SALE OF MORTGAGE LOANS; PAYMENT OF PURCHASE PRICE

         SECTION 2.1 SALE OF MORTGAGE LOANS.

         The Seller, concurrently with the execution and delivery of this
Purchase Agreement, does hereby sell, assign, set over, and otherwise convey to
the Purchaser, without recourse, all of its right, title and interest in, to and
under the following, whether now existing or hereafter acquired and wherever
located: the Mortgage Loans, including the related Cut-Off Date Loan Balances,
and all payments in respect of the Mortgage Loans received on and after the
Cut-Off Date (exclusive of payments in respect of interest on the Mortgage Loans
accrued prior to the Cut-Off Date and received thereafter); property which
secured a Mortgage Loan and which has been acquired by foreclosure or deed in
lieu of foreclosure; the interest of the Seller in any insurance policies in
respect of the Mortgage Loans; all rights under any guaranty executed in
connection with a Mortgage Loan; and all proceeds of the foregoing.

         SECTION 2.2 RESERVED.

         SECTION 2.3 OBLIGATIONS OF SELLER UPON SALE.

         In connection with any transfer pursuant to Section 2.1 hereof, the
Seller further agrees, at its own expense, on or prior to the Closing Date, (a)
to indicate in its books and records that the related Mortgage Loans have been
sold to the Purchaser or to the Trustee, as assignee of the Purchaser, as
applicable, pursuant to this Purchase Agreement and (b) to deliver to the
Purchaser a computer file containing a true and complete list of all such
Mortgage Loans specifying for each such Mortgage Loan, as of the applicable
Cut-Off Date, (i) its account number and (ii) the related Cut-Off Date Loan
Balance. Such file, which forms a part of Exhibit D to the Pooling and Servicing
Agreement, shall also be marked as Schedule I to this Purchase Agreement and is
hereby incorporated into and made a part of this Purchase Agreement.

         The Seller agrees to prepare, execute and file UCC-1 financing
statements with the Secretary of State in the State of North Carolina (which
shall have been filed on or before the Closing Date with respect to the Mortgage
Loans) describing the applicable Mortgage Loans and naming the Seller as debtor
and, with respect to the Mortgage Loans, the Purchaser (and indicating that such
loans have been assigned to the Trustee) as secured party and all necessary
continuation statements and any amendments to the UCC-1 financing statements
required to reflect a change in the name or corporate structure of the Seller or
the filing of any additional UCC-1 financing statements due to the change in the
principal office of the Seller, as are necessary to perfect and protect the
Trustee's interest in each Mortgage Loan, the payments thereon and the proceeds
thereof.


<PAGE>   5

         In connection with any conveyance by the Seller, the Seller shall on
behalf, and at the direction of, the Purchaser deliver to, and deposit with, the
Trustee, as Document Custodian on or before the Closing Date, the following
documents or instruments with respect to each Mortgage Loan (the "Related
Documents"):

                  (i) the original Mortgage Note, endorsed "Pay to the order of
         Norwest Bank Minnesota, National Association, as trustee for the
         registered holders from time to time of FURST Mortgage Loan Trust
         1999-A, Mortgage Pass-Through Certificates, Series 1999-A, without
         recourse," signed in the name of the Seller by an authorized officer,
         with all intervening endorsements showing a complete chain of title
         from the originator of such Mortgage Loan to the Seller;

                  (ii) the original Mortgage, with evidence of recording
         thereon, provided, that if the original Mortgage has been delivered for
         recording to the appropriate public recording office of the
         jurisdiction in which the Mortgaged Property is located but has not yet
         been returned to the Seller by such recording office, the Seller shall
         cause to be delivered to the Document Custodian a certified true copy
         of such original Mortgage so certified by the Seller, together with a
         certificate of the Seller certifying that such original Mortgage has
         been so delivered to such recording office; in all such instances, the
         Seller shall deliver or cause to be delivered the original recorded
         Mortgage to the Document Custodian promptly upon receipt of the
         original recorded Mortgage;

                  (iii) the original assignment of Mortgage, from the Seller to
         "Norwest Bank Minnesota, National Association, as trustee for the
         registered holders from time to time of FURST Mortgage Loan Trust
         1999-A," which assignment shall be in form and substance acceptable for
         recording;

                  (iv) the original attorney's opinion of title or the original
         policy of title insurance, provided, that if any such original policy
         of title insurance has not yet been received by the Seller, the Seller
         shall cause to be delivered to the Document Custodian a copy of such
         policy or a title insurance binder or commitment for the issuance of
         such policy;

                  (v) originals of all intervening assignments of Mortgage, with
         evidence of recording thereon, showing a complete chain of title from
         the originator of the Mortgage Loan to the Seller, provided, that if
         any such original intervening assignment of Mortgage has been delivered
         for recording to the appropriate public recording office of the
         jurisdiction in which the Mortgaged Property is located but has not yet
         been returned to the Seller by such recording office, the Seller may
         have delivered to the Document Custodian a certified true copy of such
         original assignment of Mortgage so certified by the Seller, together
         with a certificate of the Seller certifying that such original
         assignment of Mortgage has been so delivered to such recording office;
         in all such instances, the Seller shall deliver or cause to


<PAGE>   6

         be delivered any such original assignments to the Document Custodian
         promptly upon receipt thereof; and

                  (vi) originals of all assumption and modification agreements,
         if any; provided, however, the Seller may deliver to the Document
         Custodian all of the above documents other than those referred to in
         clause (i) above (which shall be delivered on or before the Closing
         Date) within 60 days after the Closing Date.

         For all Mortgage Loans that were owned by the Seller on the Cut-Off
Date as successor by merger to the originator or previous holder, the Seller
shall deliver to the Trustee, as Document Custodian, on or before the Closing
Date, an officer's certificate identifying such Mortgage Loans and the
identities of the Persons (each, a "Merged Holder") that are reflected on the
related Mortgage Notes and Mortgage or assignment of Mortgage as the holder,
certifying that the Seller is successor by merger to each such Merged Holder and
certifying as to the authority of the officer signing the endorsement referred
to in clause (i) above and the assignment of Mortgage referred to in clause
(iii) above to execute the same. Such officer's certificate shall constitute
part of the Mortgage File of each such Mortgage Loan.

         The Seller further hereby confirms to the Purchaser that, as of the
Closing Date, it has caused the portions of the Electronic Ledger relating to
the Mortgage Loans maintained by the Master Servicer to be clearly and
unambiguously marked to indicate that the Mortgage Loans have been sold to the
Purchaser or the Trustee as assignee of the Purchaser, as applicable.

         The Purchaser hereby acknowledges its acceptance of all right, title
and interest to the Mortgage Loans and other property, now existing and
hereafter created, conveyed to it pursuant to Section 2.1.

         The parties hereto intend that (a) the transaction set forth herein
with respect to the Mortgage Loans be a sale by the Seller to the Purchaser of
all the Seller's right, title and interest in and to the Mortgage Loans and
other related property described above and (b) in the event the transaction set
forth herein with respect to the Mortgage Loans is deemed not to be a sale, the
Seller shall be deemed to have granted and does hereby grant to the Purchaser a
security interest in all of the Seller's right, title and interest in, to and
under the Mortgage Loans and other related property described above, whether now
existing or hereafter created, to secure all of the Seller's obligations
hereunder, and this Purchase Agreement shall constitute a security agreement
under applicable law.

         SECTION 2.4 PAYMENT OF PURCHASE PRICE FOR THE MORTGAGE LOANS.

         (a) In consideration of the sale of the Mortgage Loans from the Seller
to the Purchaser on the Closing Date, the Purchaser agrees to pay to the Seller
on the Closing Date by transfer of immediately available funds, an amount equal
to $212,394,583.69 (the "Purchase Price").

<PAGE>   7

                                   ARTICLE III

                         REPRESENTATIONS AND WARRANTIES;
                               REMEDIES FOR BREACH

         SECTION 3.1 SELLER REPRESENTATIONS AND WARRANTIES.

         The Seller represents and warrants to the Purchaser as of the Closing
Date and as of each Transfer Date:

               (i) It is a national banking association existing under the laws
         of the United States of America and has the requisite power and
         authority to own its assets and to transact the business in which it is
         currently engaged. It is duly qualified to do business and is in good
         standing in each jurisdiction in which the character of the business
         transacted by it or properties owned or leased by it requires such
         qualification and in which the failure so to qualify would have a
         material adverse effect on (a) its business, properties, assets, or
         condition (financial or other), (b) its performance of its obligations
         under this Purchase Agreement, (c) the value or marketability of the
         Mortgage Loans and (d) the ability to foreclose on the related
         Mortgaged Properties;

              (ii) It has the power and authority to make, execute, deliver and
         perform this Purchase Agreement and all of the transactions
         contemplated under this Purchase Agreement, and has taken all necessary
         action to authorize the execution, delivery and performance of this
         Purchase Agreement. When executed and delivered, this Purchase
         Agreement will constitute its legal, valid and binding obligation
         enforceable in accordance with its terms, except as enforcement of such
         terms may be limited by bankruptcy, insolvency or similar laws
         affecting the enforcement of creditors' rights generally and by the
         availability of equitable remedies;

             (iii) It holds all necessary licenses, certificates and permits
         from all government authorities necessary for conducting its business
         as it is presently conducted. It is not required to obtain the consent
         of any other party or any consent, license, approval or authorization
         from, or registration or declaration with, any governmental authority,
         bureau or agency in connection with the execution, delivery,
         performance, validity or enforceability of this Purchase Agreement,
         except for such consents, licenses, approvals or authorizations, or
         registrations or declarations, as shall have been obtained or filed, as
         the case may be, prior to the Closing Date;

              (iv) The execution, delivery and performance of this Purchase
         Agreement by it will not conflict with or result in a breach of, or
         constitute a default under, any provision of any existing law or
         regulation or any order or decree of any court applicable to it or any
         of


<PAGE>   8

         its properties or any provision of its Articles of Association or
         Bylaws, or constitute a material breach of, or result in the creation
         or imposition of any lien, charge or encumbrance upon any of its
         properties pursuant to, any mortgage, indenture, contract or other
         agreement to which it is a party or by which it may be bound;

               (v) No litigation or administrative proceeding of or before any
         court, tribunal or governmental body is currently pending, or to its
         knowledge threatened, against it or any of its properties or with
         respect to this Purchase Agreement or the Certificates which in its
         opinion has a reasonable likelihood of resulting in a material adverse
         effect on the transactions contemplated by this Purchase Agreement;

              (vi) The transactions contemplated by this Purchase Agreement are
         in the ordinary course of business of the Seller; and

             (vii) The Seller is not insolvent, nor will it be made insolvent by
         the transfer of the Mortgage Loans, nor is the Seller aware of any
         pending insolvency.

                  It is understood and agreed that the representations and
         warranties set forth in this Section 3.1 shall survive delivery of the
         Mortgage Files to the Document Custodian on behalf of the Purchaser.

         SECTION 3.2 SELLER REPRESENTATIONS AND WARRANTIES RELATING TO THE
MORTGAGE LOANS.

         The Seller represents and warrants to the Purchaser that, as of the
Closing Date with respect to the Mortgage Loans it has made the representations
and warranties set forth in Section 2.6(a) of the Pooling and Servicing
Agreement for the benefit of the Purchaser or the Trustee as applicable. Such
representations and warranties are incorporated by reference in this Section
3.2, and the Purchaser may rely thereon as if such representations and
warranties were fully set forth herein.

         With respect to the representations and warranties set fort in this
Section 3.2 that are made to the best of the Seller's knowledge or as to which
the Seller has no knowledge, if it is discovered by the Purchaser, the Seller,
the Master Servicer, the Trust Administrator or a Responsible Officer of the
Trustee that the substance of any such representation and warranty is inaccurate
and such inaccuracy materially and adversely affects the value of the related
Mortgage Loan then notwithstanding the Seller's lack of knowledge with respect
to the substance of such representation and warranty being inaccurate at the
time the representation or warranty was made, such inaccuracy shall be deemed a
breach of the applicable representation or warranty and with respect to any
breach of such representation or warranty or of any other representation or
warranty, the Seller shall cure, repurchase or substitute in accordance with the
Pooling and Servicing Agreement.


<PAGE>   9

         It is understood and agreed that the representations and warranties set
forth in this Section 3.2 shall survive delivery of the respective Mortgage
Files to the Document Custodian on behalf of the Purchaser.


                                   ARTICLE IV

                               SELLER'S COVENANTS


         SECTION 4.1 COVENANTS OF THE SELLER.

         (a) The Seller hereby covenants that except for the transfer hereunder,
the Seller will not sell, pledge, assign or transfer to any other Person, or
grant, create, incur, assume or suffer to exist any Lien on any Mortgage Loan,
or any interest therein; the Seller will notify the Trustee, as assignee of the
Purchaser, of the existence of any Lien on any Mortgage Loan immediately upon
discovery thereof; and the Seller will defend the right, title and interest of
the Trust Fund, as assignee of the Purchaser, in, to and under the Mortgage
Loans, against all claims of third parties claiming through or under the Seller;
provided, however, that nothing in this Section 4.1 shall prevent or be deemed
to prohibit the Seller from suffering to exist upon any of the Mortgage Loans
any Liens for municipal or other local taxes and other governmental charges if
such taxes or governmental charges shall not at the time be due and payable or
if the Seller shall currently be contesting the validity thereof in good faith
by appropriate proceedings and shall have set aside on its books adequate
reserves with respect thereto.

         (b) During the period commencing on the first day of the offering of
the Senior Certificates, the Class M Certificates, the Class B-1 Certificates
and the Class B-2 Certificates (collectively the "Offered Certificates") to the
public and ending on the Closing Date, the Seller shall not, without the prior
written consent of First Union Capital Markets Corp., ("FCMC") sell or enter
into agreements with other underwriters (other than FCMC and PaineWebber
Incorporated) to sell mortgage pass-through securities, collateralized mortgage
obligations or similar securities representing interests in or secured by
residential mortgage loans purchased or originated by the Seller.

                                    ARTICLE V

                                MASTER SERVICING

         SECTION 5.1 MASTER SERVICING.

         First Union National Bank will be the Master Servicer of the Mortgage
Loans pursuant to the terms and conditions of the Pooling and Servicing
Agreement.



<PAGE>   10

                                   ARTICLE VI

               INDEMNIFICATION WITH RESPECT TO THE MORTGAGE LOANS

         SECTION 6.1 INDEMNIFICATION.

         (a) The Seller agrees to indemnify and hold harmless the Purchaser,
each of its directors, each of its officers who have signed the registration
statement, and each of its directors and each person or entity who controls the
Purchaser or any such person, within the meaning of Section 15 of the Securities
Act of 1933, as amended (the "Securities Act"), against any and all losses,
claims, damages or liabilities, joint and several, to which the Purchaser, or
any such person or entity may become subject, under the Securities Act or
otherwise, and will reimburse the Purchaser and each such controlling person for
any legal or other expenses incurred by the Purchaser or such controlling person
in connection with investigating or defending any such loss, claims, damages or
liabilities insofar as such losses, claims, damages or liabilities (or actions
in respect thereof) arise out of or are based upon any untrue statement or
alleged untrue statement of any material fact contained in the Prospectus
Supplement or any amendment or supplement to the Prospectus Supplement approved
in writing by the Seller or the omission or the alleged omission to state
therein a material fact necessary in order to make the statements in the
Prospectus Supplement or any amendment or supplement to the Prospectus
Supplement approved in writing by the Seller, in the light of the circumstances
under which they were made, not misleading, but only to the extent that such
untrue statement or alleged untrue statement or omission or alleged omission
relates to the information contained in the Prospectus Supplement under the
captions: "Summary of Terms--The Mortgage Loans," "Risk Factors" (other than
"--Book-Entry System; and "--Certificate Ratings"), "The Seller and the Master
Servicer" and "The Mortgage Loan Pool" and the corresponding information in the
"Summary of Terms" (such information, the "Seller Information"). This indemnity
agreement will be in addition to any liability which the Seller may otherwise
have.

         (b) The Purchaser agrees to indemnify and hold harmless the Seller
against any and all losses, claims, damages or liabilities, joint and several,
to which the Seller, or any such person or entity may become subject, under the
Securities Act or otherwise, and will reimburse the Seller for any legal or
other expenses incurred by the Seller or such controlling person in connection
with investigating or defending any such losses, claims, damages or liabilities
insofar as such losses, claims, damages or liabilities (or actions in respect
thereof) arise out of or are based upon any untrue statement or alleged untrue
statement of any material fact contained in the Prospectus Supplement or any
amendment or supplement to the Prospectus Supplement or the omission or the
alleged omission to state therein a material fact necessary in order to make the
statements in the Prospectus Supplement or any amendment or supplement to the
Prospectus Supplement, in the light of the circumstances under which they were
made, not misleading, but only to the extent that such


<PAGE>   11

untrue statement or alleged untrue statement or omission or alleged omission
relates to the information contained in the Prospectus Supplement other than the
Seller Information. This indemnity agreement will be in addition to any
liability which the Purchaser may otherwise have.

         (c) Promptly after receipt by any indemnified party under this Article
VI of notice of any claim or the commencement of any action, such indemnified
party shall, if a claim in respect thereof is to be made against any
indemnifying party under this Article VI, notify the indemnifying party in
writing of the claim or the commencement of that action; provided, however, that
the failure to notify an indemnifying party shall not relieve it from any
liability which it may have under this Article VI except to the extent it has
been materially prejudiced by such failure and, provided further, that the
failure to notify any indemnifying party shall not relieve it from any liability
which it may have to any indemnified party otherwise than under this Article VI.

         If any such claim or action shall be brought against an indemnified
party, and it shall notify the indemnifying party thereof, the indemnifying
party shall be entitled to participate therein and, to the extent that it
wishes, jointly with any other similarly notified indemnifying party, to assume
the defense thereof with counsel reasonably satisfactory to the indemnified
party. After notice from the indemnifying party to the indemnified party of its
election to assume the defense of such claim or action, the indemnifying party
shall not be liable to the indemnified party under this Article VI for any legal
or other expenses subsequently incurred by the indemnified party in connection
with the defense thereof other than reasonable costs of investigation.

         Any indemnified party shall have the right to employ separate counsel
in any such action and to participate in the defense thereof, but the fees and
expenses of such counsel shall be at the expense of such indemnified party
unless: (i) the employment thereof has been specifically authorized by the
indemnifying party in writing; (ii) such indemnified party shall have been
advised by such counsel that there may be one or more legal defenses available
to it which are different from or additional to those available to the
indemnifying party and in the reasonable judgment of such counsel it is
advisable for such indemnified party to employ separate counsel; or (iii) the
indemnifying party has failed to assume the defense of such action and employ
counsel reasonably satisfactory to the indemnified party, in which case, if such
indemnified party notifies the indemnifying party in writing that it elects to
employ separate counsel at the expense of the indemnifying party, the
indemnifying party shall not have the right to assume the defense of such action
on behalf of such indemnified party, it being understood, however, the
indemnifying party shall not, in connection with any one such action or separate
but substantially similar or related actions in the same jurisdiction arising
out of the same general allegations or circumstances, be liable for the
reasonable fees and expenses of more than one separate firm of attorneys (in
addition to local counsel) at any time for all such indemnified parties, which
firm shall be designated in writing by the Purchaser, if the indemnified parties
under this Article VI consist of the Purchaser, or by the Seller, if the
indemnified parties under this Article VI consist of the Seller.


<PAGE>   12

         Each indemnified party, as a condition of the indemnity agreements
contained in Section 6.1(a) and (b), shall use its best efforts to cooperate
with the indemnifying party in the defense of any such action or claim. No
indemnifying party shall be liable for any settlement of any such action
effected without its written consent (which consent shall not be unreasonably
withheld), but if settled with its written consent or if there be a final
judgment for the plaintiff in any such action, the indemnifying party agrees to
indemnify and hold harmless any indemnified party from and against any loss or
liability by reason of such settlement or judgment.

         Notwithstanding the foregoing sentence, if at any time an indemnified
party shall have requested an indemnifying party to reimburse the indemnified
party for fees and expenses of counsel, the indemnifying party agrees that it
shall be liable for any settlement of any proceeding effected without its
written consent if (i) such settlement is entered into more than 30 days after
receipt by such indemnifying party of the aforesaid request and (ii) such
indemnifying party shall not have reimbursed the indemnified party in accordance
with such request prior to the date of such settlement.

         (d) In order to provide for just and equitable contribution in
circumstances in which the indemnity agreement provided for in this Article VI
is for any reason held to be unenforceable although applicable in accordance
with its terms, the Seller, on the one hand, and the Purchaser, on the other,
shall contribute to the aggregate losses, liabilities, claims, damages and
expenses of the nature contemplated by said indemnity agreement incurred by the
Seller and the Purchaser in such proportions as shall be appropriate to reflect
the relative benefits received by the Seller, on the one hand, and the
Purchaser, on the other, from the sale of the Mortgage Loans such that the
Purchaser is responsible for that portion represented by the percentage that the
underwriting discount with respect to the Offered Certificates (the
"Underwriting Discount") bears to the sum of the Purchase Price and the
Underwriting Discount and the Seller shall be responsible for the balance;
provided, however, that no person guilty of fraudulent misrepresentation (within
the meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation. For purposes of this Section, each person, if any, who
controls the Purchaser within the meaning of Section 15 of the Securities Act
shall have the same rights to contribution as the Purchaser and each director of
the Seller, each officer of the Seller, and each person, if any, who controls
the Seller within the meaning of Section 15 of the Securities Act shall have the
same rights to contribution as the Seller. Notwithstanding anything in this
paragraph (d) to the contrary, the Purchaser shall not be required to contribute
an amount in excess of the amount of the Underwriting Discount.

         (e) The Seller agrees to indemnify and to hold each of the Purchaser,
the Trustee, each Certificateholder and the Master Servicer harmless against any
and all claims, losses, penalties, fines, forfeitures, legal fees and related
costs, judgments, and any other costs, fees and expenses that the Purchaser, the
Trustee and any Certificateholder may sustain in any way (i) related to the
failure of the Seller to perform its duties in compliance with the terms of this
Purchase Agreement or (ii) arising from a breach by the Seller of its
representations and warranties in Article III of this


<PAGE>   13

Purchase Agreement. The Seller shall immediately notify the Purchaser, the
Trustee and each Certificateholder if a claim is made by a third party with
respect to this Purchase Agreement, the Seller shall assume the defense of any
such claim and pay all expenses in connection therewith, including reasonable
counsel fees, and promptly pay, discharge and satisfy any judgment or decree
which may be entered against the Purchaser, the Master Servicer, the Seller, the
Trustee and/or Certificateholder in respect of such claim.


                                   ARTICLE VII

                                   TERMINATION

         SECTION 7.1 TERMINATION.

         The respective obligations and responsibilities of the Seller and the
Purchaser created hereby shall terminate, except for the Seller's and the
Purchaser's indemnity obligations as provided herein, upon the termination of
the Trust Fund as provided in Article X of the Pooling and Servicing Agreement.


                                  ARTICLE VIII

                            MISCELLANEOUS PROVISIONS

         SECTION 8.1 AMENDMENT.

         This Purchase Agreement may be amended from time to time by the Seller
and the Purchaser by written agreement signed by the Seller and the Purchaser.

         SECTION 8.2 GOVERNING LAW.

         THIS PURCHASE AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NORTH CAROLINA AND THE OBLIGATIONS,
RIGHTS AND REMEDIES OF THE PARTIES HEREUNDER SHALL BE DETERMINED IN ACCORDANCE
WITH SUCH LAWS.

         SECTION 8.3 NOTICES.

         All demands, notices and communications hereunder shall be in writing
and shall be deemed to have been duly given if personally delivered at or mailed
by registered mail, postage prepaid, addressed as follows:


<PAGE>   14

                      if to the Seller:

                      First Union National Bank
                      One First Union Center
                      Charlotte, North Carolina  28288
                      Attention:  Patrick J. Tadie

or, such other address as may hereafter be furnished to the Purchaser in writing
by the Seller.

                      if to the Purchaser:

                      First Union Residential Securitization Transactions, Inc.
                      One First Union Center
                      Charlotte, North Carolina  28288-0600
                      Attention:  Patrick J. Tadie

or such other address as may hereafter be furnished to the Seller in writing by
the Purchaser.

         SECTION 8.4 SEVERABILITY OF PROVISIONS.

         If any one or more of the covenants, agreements, provisions of terms of
this Purchase Agreement shall be held invalid for any reason whatsoever, then
such covenants, agreements, provisions or terms shall be deemed severable from
the remaining covenants, agreements, provisions or terms of this Purchase
Agreement and shall in no way affect the validity of enforceability of the other
provisions of this Purchase Agreement.

         SECTION 8.5 COUNTERPARTS.

         This Purchase Agreement may be executed in one or more counterparts and
by the different parties hereto on separate counterparts, each of which, when so
executed, shall be deemed to be an original and such counterparts, together,
shall constitute one and the same agreement.

         SECTION 8.6 FURTHER AGREEMENTS.

         The Purchaser and the Seller each agree to execute and deliver to the
other such additional documents, instruments or agreements as may be necessary
or reasonable and appropriate to effectuate the purposes of this Purchase
Agreement or in connection with the issuance of any series of Certificates
representing interests in the Mortgage Loans.


<PAGE>   15

         SECTION 8.7 INTENTION OF THE PARTIES.

         It is the intention of the parties that the Purchaser is purchasing,
and the Seller is selling, the Mortgage Loans rather than pledging the Mortgage
Loans to secure a loan by the Purchaser to the Seller. Accordingly, the parties
hereto each intend to treat the transaction for federal income tax purposes and
all other purposes as a sale by the Seller, and a purchase by the Purchaser, of
the Mortgage Loans. The Purchaser will have the right to review the Mortgage
Loans and the related Mortgage Files to determine the characteristics of the
Mortgage Loans which will affect the federal income tax consequences of owning
the Mortgage Loans and the Seller will cooperate with all reasonable requests
made by the Purchaser in the course of such review.

         SECTION 8.8 SUCCESSORS AND ASSIGNS: ASSIGNMENT OF PURCHASE AGREEMENT.

         The Purchase Agreement shall bind and inure to the benefit of and be
enforceable by the Seller, the Purchaser and the Trustee. The obligations of the
Seller under this Purchase Agreement cannot be assigned or delegated to a third
party without the consent of the Purchaser, which consent shall be at the
Purchaser's sole discretion, except that the Purchaser acknowledges and agrees
that the Seller may assign its obligations hereunder to any Person into which
the Seller is merged or any corporation resulting from any merger, conversion or
consolidation to which the Seller is a party or any Person succeeding to the
business of the Seller. The parties hereto acknowledge that the Purchaser is
acquiring the Mortgage Loans for the purpose of contributing them to a trust
that will issue a series of Certificates representing undivided interests in
such Mortgage Loans. As an inducement to the Purchaser to purchase the Mortgage
Loans, the Seller acknowledges and consents to the assignment by the Purchaser
to the Trustee of all of the Purchaser's rights against the Seller pursuant to
this Purchase Agreement insofar as such rights relate to Mortgage Loans
transferred to such Trustee and to the enforcement or exercise of any right or
remedy against the Seller pursuant to this Purchase Agreement by the Trustee
under the Pooling and Servicing Agreement. Such enforcement of a right or remedy
by the Trustee shall have the same force and effect as if the right or remedy
had been enforced or exercised by the Purchaser directly. The parties
acknowledge and agree that the Trustee is an intended third party beneficiary of
this Purchase Agreement (including, specifically, the indemnification provisions
of Section 6.1(e)) and that the Trustee shall be entitled to enforce the
provisions of this Purchase Agreement against the parties hereto.

         SECTION 8.9 SURVIVAL.

         The representations and warranties set forth in Article III and the
provisions of Article VI shall survive the purchase of the Mortgage Loans
hereunder.


<PAGE>   16

         IN WITNESS WHEREOF, the Seller and the Purchaser have caused their
names to be signed to this Purchase Agreement by their respective officers
thereunto duly authorized as of the day and year first above written.

                                             FIRST UNION RESIDENTIAL
                                             SECURITIZATION TRANSACTIONS, INC.,
                                               as Purchaser


                                             By:    /s/ Patrick J. Tadie
                                                --------------------------------
                                             Name:  Patrick J. Tadie
                                             Title:    Vice President


                                             FIRST UNION NATIONAL BANK,
                                             as Seller


                                             By:    /s/ Patrick J. Tadie
                                                --------------------------------
                                             Name:  Patrick J. Tadie
                                             Title:    Vice President



<PAGE>   17


STATE OF NORTH CAROLINA    )
                           )ss.:
MECKLENBURG COUNTY         )


         On the 25th day of February, 1999 before me, a Notary Public in and for
said State, personally appeared Patrick Tadie, known to me to be a Vice
President of FIRST UNION RESIDENTIAL SECURITIZATION TRANSACTIONS, INC., the
corporation that executed the within instrument, and also known to me to be the
person who executed it on behalf of said corporation, and acknowledged to me
that such corporation executed the within instrument.

         IN WITNESS WHEREOF, I have hereunto set my hand and affixed my official
seal the day and year in this certificate first above written.



/s/ Tina M. Cox
---------------------------------------
Notary Public


(NOTARIAL SEAL)


Commission Expires: 8/6/2003

<PAGE>   18

STATE OF NORTH CAROLINA    )
                           )ss.:
MECKLENBURG COUNTY         )


         On the 25th day of February, 1999 before me, a Notary Public in and for
said State, personally appeared Patrick Tadie, known to me to be a Vice
President of FIRST UNION NATIONAL BANK, the national banking association that
executed the within instrument, and also known to me to be the person who
executed it on behalf of said corporation, and acknowledged to me that such
national banking association executed the within instrument.

         IN WITNESS WHEREOF, I have hereunto set my hand and affixed my official
seal the day and year in this certificate first above written.


/s/ Tina M. Cox
---------------------------------------
Notary Public


(NOTARIAL SEAL)


Commission Expires: 8/6/2003


<PAGE>   19


                                   SCHEDULE I


                                 MORTGAGE LOANS