<PAGE>   1

                                                                    EXHIBIT 10.4

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                          T&W LEASE BACKED TRUST 1997-1


                            LEASE BACKED CERTIFICATES


                         CERTIFICATE PURCHASE AGREEMENT


                           T&W FINANCIAL CORPORATION,
                                   as Company,

                         T&W FUNDING COMPANY 1, L.L.C.,
                                  as Transferor

                                       and

                       CENTRE SQUARE FUNDING CORPORATION,
                                  as Purchaser

                          Dated as of February 7, 1997



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<PAGE>   2

                      TABLE OF CONTENTS

<TABLE>
<CAPTION>

<S>           <C>                                                                      <C>
Section 1.    Agreement to Purchase.................................................   2  
                                                                                          
Section 2.    Delivery and Payment..................................................   2  
                                                                                          
Section 3.    Purchase Price........................................................   2  
                                                                                          
Section 4.    Representations, Warranties and Agreements of the Transferor..........   3  
                                                                                          
Section 5.    Representations, Warranties and Agreements of the Company.............   4  
                                                                                          
Section 6.    Representations, Warranties and Agreements of the Purchaser...........   7  
                                                                                          
Section 7.    Conditions of the Purchaser's Obligation to Make the Initial Purchase.   8  
                                                                                          
Section 8.    Conditions to the Purchaser's Obligation to Make Additional Purchases.  10  
                                                                                          
Section 9.    Intention of the Parties..............................................  10  
                                                                                          
Section 10.   Expenses..............................................................  11  
                                                                                          
Section 11.   Survival..............................................................  11  
                                                                                          
Section 12.   Notices...............................................................  11  
                                                                                          
Section 13.   Severability of Provisions............................................  12  
                                                                                          
Section 14.   Counterparts..........................................................  12  
                                                                                          
Section 15.   Governing Law.........................................................  12  
                                                                                          
Section 16.   Successors and Assigns................................................  12  
                                                                                          
Section 17.   Waiver: Prior Agreements..............................................  12  
                                                                                          
Section 18.   Further Agreements....................................................  12  
                                                                                          
Section 19.   General Interpretive Principles ......................................  13  
                                                                                          
Section 20.   Bankruptcy............................................................  13  

</TABLE>



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<TABLE>

<S>           <C>                                                                     <C>
Section 21.   Limited Recourse......................................................  14
Section 22.   Amendments............................................................  14

</TABLE>



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<PAGE>   4

                          T&W FUNDING COMPANY I, L.L.C.

                          T&W Lease Backed Trust 1997-1

                            Lease Backed Certificates

                         CERTIFICATE PURCHASE AGREEMENT


                                                   Dated: as of February 7, 1997



To the Purchaser named
on the signature page attached hereto


Ladies and Gentlemen:


            T&W Funding Company I, L.L.C. (the "Transferor") proposes, subject
to the terms and conditions stated herein, to cause the Trust (as defined
herein) to sell to you (the "Purchaser"), up to $100,000,000 principal amount of
certificates (the "Commitment"), from time to time and as shall be agreed upon
by the parties hereto, entitled 8.275% Lease-Backed Certificates (the
"Certificates") issued by T&W Lease-Backed Trust 1997-1 (the "Trust"). The
Certificates will evidence undivided ownership interests in the Trust, the
corpus of which will include, among other things, the fight to receive certain
payments which are due after January 1, 1997, or such later date specified on an
Additional Purchase Certificate (as defined below) (each, a "Cut-Off Date")
under a pool of equipment and vehicle leases ("Asset Interests"), which will be
sold from time to time by the Transferor to the Trust pursuant to a Trust and
Security Agreement, dated as of February 1, 1997 (the "Trust and Security
Agreement"), among the Transferor, T&W Financial Corporation (the "Servicer"),
as Servicer, and Norwest Bank Minnesota, National Association (the "Trustee"),
as Trustee and as Backup Servicer. Such Trust and Security Agreement also will
convey to the Trust a security interest in the Lease Contracts and the Equipment
(as such terms are defined in the Trust and Security Agreement) leased pursuant
to the Lease Contracts (or an assignment of a security interest in such
Equipment). Each of the Transferor and the Servicer, in recognition of the
benefits expected to accrue to it from the consummation of the transactions
contemplated by the Trust and Security Agreement, makes the representations,
warranties and covenants set forth in this Agreement.


            All capitalized terms used herein that are not otherwise defined
herein shall have the respective meanings set forth in the Trust and Security
Agreement.



<PAGE>   5

Section 1.  Agreement to Purchase.

            Subject to the terms and conditions and in reliance upon the
representations and warranties herein set forth, on the date hereof, the
Transferor agrees to cause the Trust to sell to the Purchaser, and the Purchaser
agrees to purchase, the Certificates having the Percentage Interest as of the
initial Cut-Off Date in the amount set forth in Schedule I hereto (the "Initial
Purchase").

            For a period of time not to exceed the Funding Period (as defined in
the Trust and Security Agreement), on any date occurring subsequent to the
Closing Date (as defined below), the Transferor may sell additional Asset
Interests to the Trust and cause the principal balance of the Certificates to
increase in a cumulative principal amount up to the Commitment (each, an
"Additional Purchase"). The Transferor shall, not later than five business days
prior to the intended Delivery Date (as defined below), notify the Purchaser of
its intention to cause an Additional Purchase to occur by delivery of an
Additional Purchase Certificate (each an "Additional Purchase Certificate"),
setting forth the amount of such Additional Purchase, the intended Delivery
Date, the related Cut-Off Date and the date that a new Lease Schedule will be
available. Upon receipt by the Purchaser of an Additional Purchase Certificate,
such Additional Purchase shall occur (in an aggregate principal amount not to
exceed the Commitment), subject to satisfaction of the terms and conditions
contained herein.

Section 2.  Delivery and Payment.

            Delivery of the Certificates shall be made at the offices of Chapman
and Cutler, 111 West Monroe, Chicago, Illinois 60603, at 10:00 a.m., Chicago
time, on February 6, 1997 (the "Closing Date"). The Closing Date and the date of
each Additional Purchaser are each referred to herein as a "Delivery Date."

            Upon fulfillment of the foregoing and satisfaction of all conditions
specified in Section 7 of this Agreement, with respect to the Initial Purchase,
and Section 8 of this Agreement with respect to each Additional Purchase, the
Purchaser shall pay to the Transferor the Purchase Price set forth in Section 3
of this Agreement.

Section 3. Purchase Price.

            The Purchase Price for the Certificates purchased by the Purchaser
shall be 100% of the principal amount thereof (or such other amount as the
Transferor and the Purchaser may agree in writing).

            Payment of the Purchase Price shall be made by the Purchaser by wire
transfer of immediately available funds against delivery to the Purchaser of
such Certificates (or in the case of an Additional Purchase, following an
increase in the principal balance of the Certificates).



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<PAGE>   6

Section 4. Representations, Warranties and Agreements of the Transferor.

            The Transferor represents and warrants to, and agrees with, the
Purchaser that, as of each Delivery Date:

                  (a) Under generally accepted accounting principles, the
      Transferor will report on its books the transfer of the Lease Receivables
      to the Trust pursuant to the Trust and Security Agreement and the sale of
      the Certificates as a sale of all of its right, title and interest in such
      Lease Receivables. The Transferor has been advised by its independent
      certified public accountants that they do not disagree with such treatment
      based on Statement No. 125 of the Financial Accounting Standards Board;

                  (b) The Lease Schedule, created as of January 1, 1997 with
      respect to the Initial Purchase, and each Additional Purchase Certificate
      as of the related Cut-Off-Date set forth on such Additional Purchase
      Certificate with respect to each Additional Purchase, which has been made
      available to you by the Transferor was complete as of the date thereof and
      includes in accurate description of the Lease Contracts in which a
      security interest is being transferred to the Trust under the Trust and
      Security Agreement;

                  (c) The Certificates will be duly and validly authorized and,
      when the Certificates are executed, issued, authenticated and delivered
      pursuant to the Trust and Security Agreement and this Purchase Agreement,
      such Certificates will be duly and validly entitled to the benefits of the
      Trust and Security Agreement and to the benefits of the Certificate
      Guaranty Insurance Policy Number 23074 (the "Surety Bond"), issued by MBIA
      Insurance Corporation ("MBIA");

                  (d) The representations and warranties made by the Transferor
      in the Contribution Agreement, the Insurance Agreement and the Trust and
      Security Agreement are true and correct in all material respects on the
      related Delivery Date;

                  (e) Any taxes, fees and other governmental charges payable by
      the Transferor in connection with the execution and delivery of the
      Contribution Agreement, the Trust and Security Agreement and this Purchase
      Agreement, the transfer of the Trust Property to the Trust, and the
      execution, delivery and sale of the Certificates, have been or will be
      paid at or prior to the related Delivery Date;

                  (f) Neither the Transferor nor anyone acting on its behalf has
      offered, transferred, pledged, sold or otherwise disposed of any
      Certificate, any interest in any Certificate or any other similar
      security, or solicited any offer to buy or accept a transfer, pledge or
      other disposition of any Certificate, any interest in any Certificate or
      any other similar security from, or otherwise approached or negotiated
      with respect to any Certificate, any interest in any Certificate of any
      other similar security with, any person in any manner, or made any general
      solicitation by means of general advertising or in any



                                       -3-

<PAGE>   7

      other manner, or taken any other action which would constitute a
      distribution of the Certificates under the Securities Act of 1933, as
      amended (the "1933 Act"), or which would render the disposition of the
      Certificates a violation of Section 5 of the 1933 Act or require
      registration pursuant thereto, require qualification of the Trust and
      Security Agreement under the Trust Indenture Act of 1939, or require
      registration of the Trust under the Investment Company Act of 1940, nor
      will the Transferor act, nor has it authorized or will it authorize any
      person to act, in such manner with respect to any Certificate;

                  (g) The Transferor will own on each Delivery Date the Trust
      Property being conveyed to the Trust under the Trust and Security
      Agreement on such date (other than Equipment or Leased Leased Vehicles not
      owned by the Company on such date), free and clear of any lien, mortgage,
      pledge, charge, security interest or other encumbrance, and will not have
      assigned, conveyed, pledged or otherwise transferred to any other person
      any of its right, title or interest in such Trust Property or in such
      Trust and Security Agreement or the Certificates being issued pursuant
      thereto; the Transferor has full power and authority to convey all right,
      title and interest of the Transferor in such Trust Property to the Trust
      under the Trust and Security Agreement and has duly authorized each such
      conveyance to the Trustee by all necessary corporate action; and

                  (h) On each Delivery Date, the Trust Property purported to be
      transferred on such date will have been duly and validly conveyed by the
      Transferor to the Trustee under the Trust and Security Agreement, and the
      Trust and Security Agreement will convey to the Trustee, for the benefit
      of the Holders of the Certificates, all right, title and interest of the
      Transferor in and to such Trust Property and any distributions thereon and
      income and proceed, thereof, free and clear of the claims of any persons
      (including creditors of the Transferor) and the Transferor will have
      granted to the Trustee a valid, perfected, first priority security
      interest in the related Lease Contracts and granted or assigned to the
      Trustee a valid security interest in each item of related Equipment or
      Vehicle, perfected to the extent specified in Section 4.03 of the Trust
      and Security Agreement, but such security interest may be subject to (a)
      liens for taxes arising under the laws of the state in which a Contract
      was originated or to which the related Equipment or Vehicle may have been
      relocated and (b) other liens, security interests or encumbrances that are
      given priority over a properly perfected security interest under the laws
      of the state in which any Equipment or Vehicle shall be located from time
      to time.

Section 5. Representations, Warranties and Agreements of the Company.

            The Company represents and warrants to, and agrees with, the
Purchaser that, as of each Delivery Date:

                  (a) The Company is a corporation duly organized, validly
      existing, and in good standing under the laws of the State of Washington
      with its chief executive office



                                       -4-

<PAGE>   8

      located at 6416 Pacific Heights E., Tacoma, Washington 98424, and has the 
      power to own its assets and to transact the business in which it is 
      presently engaged;

                  (b) The Company has the power, authority and legal right to
      execute, deliver and perform the Contribution Agreement, the Trust and
      Security Agreement, the Servicing Agreement, the Insurance Agreement, the
      Interest Rate Hedge Assignment dated as of February 7, 1997 between the
      Company and CoreStates Bank, N.A., as Collateral Agent (the "Hedge
      Assignment") and this Purchase Agreement, and the execution, delivery, and
      performance of the Contribution Agreement, the Trust and Security
      Agreement, the Servicing Agreement, the Insurance Agreement, the Hedge
      Assignment and this Purchase Agreement have been duly authorized by the
      Company by all necessary corporate action;

                  (c) Each of the Contribution Agreement, the Trust and Security
      Agreement, the Servicing Agreement, the Hedge Assignment, the Insurance
      Agreement, and this Purchase Agreement, assuming due authorization,
      execution and delivery by the other parties thereto, constitutes a legal,
      valid and binding obligation of the Company, enforceable against the
      Company in accordance with its terms, except that (A) such enforcement may
      be subject to bankruptcy, insolvency, reorganization, moratorium or other
      similar laws (whether statutory, regulatory or decisional) now or
      hereafter in effect relating to creditors' rights generally and (B) the
      remedy of specific performance and injunctive and other forms of equitable
      relief may be subject to certain equitable defenses and to the discretion
      of the court before which any proceeding therefor may be brought, whether
      a proceeding at law or in equity;

                  (d) The consummation of the transactions contemplated by the
      Contribution Agreement, the Trust and Security Agreement, the Servicing
      Agreement, the Insurance Agreement, the Hedge Assignment and this Purchase
      Agreement and the fulfillment of the terms therein will not conflict with
      or result in any breach of any of the terms and provisions of or
      constitute (with or without notice, lapse of time or both) a default under
      the charter documents or By-Laws of the Company, or any indenture,
      agreement, mortgage, deed of trust or other instrument to which the
      Company is a party or by which it is bound, or result in the creation or
      imposition of any lien, claim or encumbrance upon any of its material
      properties pursuant to the terms of any such indenture, agreement,
      mortgage, deed of trust or other such instrument, other than as created
      pursuant to the Contribution Agreement and the Trust and Security
      Agreement, or violate any law or any order, rule or regulation applicable
      to the Company of any court or of any federal or state regulatory body,
      administrative agency or other governmental instrumentality having
      jurisdiction over the Company or any of its properties; and there are no
      legal or governmental proceedings pending or, to the best knowledge of the
      Company, threatened or contemplated that would result in a material
      modification, suspension or revocation thereof,



                                       -5-

<PAGE>   9

                  (e) There are no proceedings or investigations to which the
      Company, or any of the Company's Affiliates, is a party pending, or, to
      the knowledge of the Company, threatened, before any court, regulatory
      body, administrative agency or other tribunal or governmental
      instrumentality (A) asserting the invalidity of the Contribution
      Agreement, the Trust and Security Agreement, the Servicing Agreement, the
      Insurance Agreement, the Hedge Assignment, this Purchase Agreement or the
      Certificates, (B) seeking to prevent the issuance of the Certificates or
      the consummation of any of the transactions contemplated by the
      Contribution Agreement, the Trust and Security Agreement, the Servicing
      Agreement, the Insurance Agreement, the Hedge Assignment, this Purchase
      Agreement or the Certificates or (C) seeking any determination or ruling
      that would materially and adversely affect the performance by the Company
      of its obligations under, or the validity or enforceability of, the
      Contribution Agreement, the Trust and Security Agreement, the Servicing
      Agreement, the Insurance Agreement, the Hedge Assignment, this Purchase
      Agreement or the Certificates;

                  (f) All approvals, authorizations, consents, orders or other
      actions of any person, corporation or other organization, or of any court,
      governmental agency or body or official, required in connection with the
      execution and delivery of the Contribution Agreement, the Trust and
      Security Agreement, the Servicing Agreement, the Insurance Agreement, the
      Hedge Assignment, and this Purchase Agreement or in connection with the
      valid and proper authorization, issuance and sale of the Certificates
      pursuant to this Purchase Agreement have been or will be taken or obtained
      on or prior to each Delivery Date;

                  (g) Under generally accepted accounting principles, the
      Company will report the contribution of the Lease Contracts and the
      Equipment by the Contributors (as defined in the Contribution Agreement)
      to the Transferor pursuant to the Contribution Agreement, the transfer of
      the Lease Receivables from the Transferor to the Trust pursuant to the
      Trust and Security Agreement, and the sale of the Certificates, as a sale
      of all of its right, title and interest in such Lease Receivables and
      Equipment. The Company has been advised by its independent certified
      public accountants that they do not disagree with such treatment based on
      Statement No. 125 of the Financial Accounting Standards Board;

                  (h) The Lease Schedule created as of January 1, 1997 with
      respect to the Initial Purchase, and each Additional Purchase Certificate
      as of the related Cut-Off Date set forth on such Additional Purchase
      Certificate with respect to each Additional Purchase, which has been made
      available to you by the Transferor was complete as of the date thereof and
      includes an accurate description of the Lease Contracts in which a
      security interest is being transferred to the Trust under the Trust and
      Security Agreement;

                  (i) When the Certificates are executed, issued, authenticated
      and delivered pursuant to the Trust and Security Agreement and this
      Purchase Agreement,



                                       -6-

<PAGE>   10

      such Certificates will be duly and validly entitled to the benefits of the
      Trust and Security Agreement and to the benefits of the Surety Bond;

                  (j) The representations and warranties made by the Company in
      the Contribution Agreement, the Servicing Agreement, the Insurance
      Agreement and the Trust and Security Agreement are true and correct in all
      material respects on each Delivery Date;

                  (k) Any taxes, fees and other governmental charges payable by
      the Company in connection with the execution and delivery of the
      Contribution Agreement, the Trust and Security Agreement, the Servicing
      Agreement, the Insurance Agreement, the Hedge Assignment, and this
      Purchase Agreement, the contribution of the Lease Assets (as defined in
      the Contribution Agreement) to the Transferor, and the execution, delivery
      and sale of the Certificates, have been or will be paid at or prior to the
      Delivery Date or;

                  (1) Neither the Company nor anyone acting on its behalf has
      offered, transferred, pledged, sold or otherwise disposed of any
      Certificate, any interest in any Certificate or any other similar
      security, or solicited any offer to buy or accept a transfer, pledge or
      other disposition of any Certificate, any interest in any Certificate or
      any other similar security from, or otherwise approached or negotiated
      with respect to any Certificate, any interest in any Certificate or any
      other similar security with, any person in any manner, or made any general
      solicitation by means of general advertising or in any other manner, or
      taken any other action which would constitute a distribution of the
      Certificates under the 1933 Act, or which would render the disposition of
      the Certificates a violation of Section 5 of the 1933 Act or require
      registration pursuant thereto, require qualification of the Trust and
      Security Agreement under the Trust Indenture Act of 1939, or require
      registration of the Trust under the Investment Company Act of 1940, nor
      will the Company act, nor has it authorized or will it authorize any
      person to act, in such manner with respect to any Certificate;

                  (m) On each Delivery Date, each of the Lease Contracts will
      meet the criteria for selection described in the Contribution Agreement;
      and

                  (n) To the extent, if any, that the rating provided with
      respect to the Certificates by the Rating Agencies is conditional upon the
      furnishing of documents or the taking of any other actions by the Company,
      the Company shall furnish such documents and take any such action.

Section 6. Representations, Warranties and Agreements of the Purchaser.

            The Purchaser hereby represents and warrants as of each Delivery
Date to the Company and the Transferor to the effect that:



                                -7-

<PAGE>   11

                  (a) The Purchaser understands that the Certificates have not
      been registered under the 1933 Act or the securities laws of any state.

                  (b) The Purchaser is acquiring its Certificate for investment
      for its own account only and not for any other person.

                  (c) The Purchaser considers itself a substantial,
      sophisticated institutional investor having such knowledge and experience
      in financial and business matters that it is capable of evaluating the
      merits and risks of investment in the Certificates.

                  (d) The Purchaser has been furnished with all information
      regarding the Certificates that it has requested from the Company, the
      Trustee or the Transferor.

                  (e) Neither the Purchaser nor anyone acting on its behalf has
      offered, transferred, pledged, sold or otherwise disposed of the
      Certificates or any interest in the Certificates or any other similar
      security to, or solicited any offer to buy or accept a transfer, pledge or
      other disposition of the Certificates, any interest in the Certificates or
      any other similar security from, or otherwise approached or negotiated
      with respect to the Certificates, any interest in the Certificates or any
      other similar security with, any person in any manner, or made any general
      solicitation by means of general advertising or in any other manner, or
      taken any other action, that would constitute a distribution of the
      Certificates under the 1933 Act or that would render the disposition of
      the Certificates a violation of Section 5 of the 1933 Act or require
      registration pursuant thereto, nor will it act, nor has it authorized or
      will it authorize any person to act, in such manner with respect to the
      Certificates.

Section 7. Conditions of the Purchaser's Obligation to Make the Initial
           Purchase.

            The Purchaser's obligation to purchase the Certificates on the
Closing Date shall be subject to the accuracy of the representations and
warranties of the Transferor and the Company herein as of the date thereof, to
the performance by the Transferor and the Company of their respective
obligations hereunder and to the following additional conditions:

                  (a) All of the respective representations and warranties of
      the Company or the Transferor contained in the Contribution Agreement,
      this Purchase Agreement, the Insurance Agreement, the Hedge Assignment,
      the Swap Agreement, the Servicing Agreement and the Trust and Security
      Agreement shall be true and correct as of the Closing Date, and no event
      shall have occurred which, with notice or the passage of time, would
      constitute a default under the Trust and Security Agreement, the Insurance
      Agreement, the Hedge Assignment, the Swap Agreement, the Servicing
      Agreement or the Contribution Agreement;



                                       -8-

<PAGE>   12

                  (b) All conditions to closing required to be fulfilled
      pursuant to Section 4.01 of the Trust and Security Agreement shall have
      been fulfilled and the Purchaser shall have received all of the documents
      and certificates (other than the original executed Lease Contracts) listed
      in such Section;

                  (c) All conditions to issuance of the Surety Bond required to
      be fulfilled pursuant to Section 3.02 of the Insurance Agreement shall
      have been fulfilled and such Surety Bond shall have been issued;

                  (d) Chapman and Cutler, special counsel for the Company and
      the Transferor, shall have furnished to the Purchaser its written
      opinions, dated the Closing Date, in form and substance satisfactory to
      the Purchaser, substantially in the forms attached hereto as Exhibit A;

                  (e) Chapman and Cutler, special counsel to the Company, shall
      have rendered directly to the Purchaser, or furnished to the Purchaser, a
      letter permitting the Purchaser's reliance on, each of its opinions
      rendered to the Rating Agencies;

                  (f) Kenneth W. McCarthy, Jr., counsel to the Company and the
      Transferor, shall have furnished to the Purchaser his written opinions,
      dated the Closing Date, in form and substance satisfactory to the
      Purchaser, substantially in the forms attached hereto as Exhibit C;

                  (g) Counsel to the Trustee, shall have furnished to the
      Purchaser his written opinion, dated the Closing Date, in form and
      substance satisfactory to the Purchaser, opining on such matters as the
      Purchaser may reasonably request;

                  (h) Kutak Rock, counsel to MBIA, shall have furnished to the
      Purchaser its written opinion, dated the Closing Date, in form and
      substance satisfactory to you, opining on such matters as you may
      reasonably request;

                  (i) The purchase of such Certificates by the Purchaser shall
      not result in a lowering of the rating of the commercial paper notes
      issued by the Purchaser and the Purchaser shall have received a letter
      from each of Moody's Investors Service ("Moody's") and Standard & Poor's
      Ratings Service, a division of the McGraw-Hill Companies ("S&P") 
      confirming their rating of such commercial paper notes;

                  (j) Any taxes, fees and other governmental charges which are
      due and payable in connection with the execution, delivery and performance
      of the Contribution Agreement, the Trust and Security Agreement, the
      Insurance Agreement, the Hedge Assignment, the Swap Agreement, the
      Purchase Agreement, the Servicing Agreement and the Certificates shall
      have been paid at or prior to the Closing Date;



                                       -9-

<PAGE>   13

                  (k) All other terms and conditions of this Purchase Agreement
      shall have been complied with;

                  (1) The Purchaser shall have received a Certificate, dated the
      Closing Date and signed by a duly authorized officer of the Transferor and
      authenticated by the Trustee, registered in the Purchaser's name or in the
      name of the Purchaser's nominee;

                  (m) On or prior to the Closing Date, the Transferor and
      Company shall have filed the financing statements described in Section
      4.01 of the Trust and Security Agreement, and all taxes and fees due in
      connection with such filing shall have been paid in full or duly provided
      for;

                  (n) All proceedings taken in connection with the sale of the
      Certificates and all documents and papers relating thereto shall be
      satisfactory to the Purchaser; and

                  (o) The Transferor shall have paid, at the closing on the
      Closing Date, the fees and disbursements of the Purchaser's special
      counsel, which are reflected in the statements of the Purchaser's special
      counsel delivered on or before the Closing Date. Promptly upon receipt of
      supplemental statements after the Closing Date, the Transferor will pay
      such additional fees and disbursements of the Purchaser's special counsel
      which were not reflected in the statements of the Purchaser's special
      counsel on the Closing Date.

Section 8. Conditions to the Purchaser's Obligation to Make Additional
           Purchases.

            The Purchaser's obligation to make Additional Purchases on any
Delivery Date shall be subject to the accuracy of the representations and
warranties of the Transferor and the Company herein as of the date thereof, and
to the performance of the Transferor and the Company of their respective
obligations hereunder and to the following additional conditions:

                  (a) All other terms and conditions of this Purchase Agreement
      shall have been complied with; and

                  (b) All conditions required to be fulfilled pursuant to
      Section 4.02 of the Trust and Security Agreement shall have been fulfilled
      and the Purchaser shall have received all of the documents and
      certificates (other than the original executed Lease Contracts) listed in
      such Section.

Section 9. Intention of the Parties.

            The Trust and Security Agreement and the Certificates have been
structured with the intention that the Certificates will qualify under
applicable tax law as indebtedness of the



                                      -10-

<PAGE>   14

Transferor, and the Transferor, the Trustee, the Servicer, any Subservicer and
the Purchaser by acceptance of its Certificate (and any person which is the
beneficial owner of any interest in a Certificate, by virtue of such person's
acquisition of a beneficial interest therein) agrees to treat the Certificates
for purposes of federal, state and local income or franchise taxes, and any
other tax imposed on or measured by income, as indebtedness of the Transferor.
The Purchaser agrees that it will cause any person acquiring an interest in a
Certificate through it to comply with this Agreement as to treatment as
indebtedness for such tax purposes.

Section 10. Expenses.

            All costs and expenses incurred in connection with the transfer and
delivery of the Trust Property and the issuance of the Certificates, including
Trustee's fees, fees for financing statement filings and continuations and the
Company's, the Trustee's, MBIA's and the Transferor's attorney's and
accountant's fees and the Purchaser's attorney's fees shall be paid by the
Company and the Transferor.

Section 11. Survival.

            The Company and the Transferor agree that the representations,
warranties and covenants made by each of them in this Agreement, in the
Contribution Agreement, in the Servicing Agreement, in the Trust and Security
Agreement, and in any document, certificate or other instrument delivered
pursuant hereto or thereto shall be deemed to be relied upon by the Purchaser,
notwithstanding any investigation heretofore or hereafter made by or on behalf
of the Purchaser, and that the representations, warranties and covenants made by
the Company and the Transferor in this Agreement, in the Trust and Security
Agreement, in the Servicing Agreement, in the Contribution Agreement, or in any
such document, certificate or other instrument shall survive the delivery of and
payment for the Certificates.

Section 12. Notices.

            (a) All communications provided for or permitted under this
Agreement shall be in writing and shall be deemed to have been daily given if
personally delivered (including by express courier) or mailed by registered
mail, postage prepaid, or transmitted by telex or telegraph and confirmed by a
similar mailed writing, if to the Purchaser, addressed to the Purchaser, at the
address set forth in Schedule I hereto, if to the Transferor, addressed to the
Transferor at 6416 Pacific Heights E., Tacoma, Washington 98424, Attention:
President, and if to the Company, addressed to the Company at 6416 Pacific
Heights E., Tacoma, Washington 98424, Attention: President or to such other
addresses as the parties may have designated in writing to the other parties.

            (b) The Transferor shall cause the instructions with respect to
payments on the Certificates and notification thereof to be reflected in the
Certificate Register, and all payments



                                      -11-

<PAGE>   15

and notifications thereof to the Purchaser, pursuant to Section 2.08 of the
Trust and Security Agreement, to be made in accordance therewith.

Section 13. Severability of Provisions.

            Any part, provision, representation, warranty or covenant of this
Agreement which is prohibited or which is held to be void or unenforceable shall
be ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof. Any part, provision,
representation, warranty or covenant of this Agreement which is prohibited or
unenforceable or held to be void or unenforceable in any jurisdiction shall, as
to such jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions hereof, and any
such prohibition or unenforceability in any jurisdiction as to this Agreement
shall not invalidate or render unenforceable such provision in any other
jurisdiction. To the extent permitted by applicable law, the parties hereto
waive any provision of law which prohibits or renders void or unenforceable any
provision hereof.

Section 14. Counterparts.

            This Agreement may be executed simultaneously in any number of
counterparts. Each counterpart shall be deemed to be an original, and all such
counterparts shall constitute one and the same instrument.

Section 15. Governing Law.

            THE AGREEMENT SHALL BE CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE
STATE OF NEW YORK AND THE OBLIGATIONS, RIGHTS AND REMEDIES OF THE PARTIES
HEREUNDER SHALL BE DETERMINED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW
YORK.

Section 16. Successors and Assigns.

            This Agreement shall inure to the benefit of and be binding upon the
parties hereto and their respective successors and assigns.

Section 17. Waiver: Prior Agreements.

            No term or provision of this Agreement may be waived or modified
unless such waiver or modification is in writing and signed by the party against
whom such waiver or modification is sought to be enforced. This Agreement
supersedes all prior agreements and understandings relating to the subject
matter hereof.

Section 18. Further Agreements.



                                      -12-

<PAGE>   16

            The Purchaser, the Transferor and the Company agree to execute and
deliver to the other such additional documents, instruments or agreements as may
be necessary or appropriate to effectuate the purposes of this Agreement.

Section 19. General Interpretive Principles.

            For purposes of this Agreement except as otherwise expressly
provided or unless the context otherwise requires:

                  (a) the terms defined in this Agreement have the meanings
      assigned to them in this Agreement and include the plural as well as the
      singular, and the use of any gender herein shall be deemed to include the
      other gender;

                  (b) accounting terms not otherwise defined herein have the
      meanings assigned to them in accordance with generally accepted accounting
      principles as in effect on the date hereof;

                  (c) references herein to "Articles," "Sections,"
      "Subsections," "paragraphs," and other subdivisions without reference to a
      document are to designated Articles, Sections, Subsections, paragraphs and
      other subdivisions of this Agreement;

                  (d) a reference to a Subsection without further reference to a
      Section is a reference to such Subsection as contained in the same Section
      in which the reference appears, and this rule shall also apply to
      paragraphs and other subdivisions;

                  (e) the words "herein," "hereof," "hereunder" and other words
      of similar import refer to this Agreement as a whole and not to any
      particular provision; and

                  (f) the term "include" or "Including" shall mean without
      limitation by reason of enumeration.

Section 20. Bankruptcy.

            (a) The Transferor and the Company under this Agreement agree that
it will not institute against, or join any person in instituting against, the
Purchaser any bankruptcy, reorganization, arrangement, insolvency or liquidation
proceeding, or other similar proceeding under the laws of any jurisdiction, for
one year and a day after the latest maturing commercial paper note relating to
the purchase of the Certificates issued by the Purchaser and outstanding is paid
in full. The obligations of the Transferor and the Company under this Section 20
shall survive termination of this Agreement.

            (b) The Purchaser agrees that during the terms of the Trust and
Security Agreement and for one year and one day after the termination of the
Trust and Security



                                      -13-

<PAGE>   17

Agreement, the Purchaser will not file any involuntary petition or otherwise
institute any bankruptcy, reorganization, arrangement, insolvency or liquidation
proceeding or other proceeding under any federal or state bankruptcy or similar
law against the Transferor.

Section 2 1. Limited Recourse.

            (a) The Purchaser agrees that the Certificates shall be limited
recourse obligations of the Transferor payable solely from the Trust Property.

            (b) The obligations of the Purchaser under this Agreement are solely
the corporate obligations of the Purchaser. No recourse shall be had for the
payment of any amount owing by the Purchaser under this Agreement or for the
payment by the Purchaser of any sums in respect hereof or any other obligation
or claim of or against the Purchaser arising out of or based upon this
Agreement, or against any affiliate, employee, officer, director, incorporator
or stockholder of the Purchaser. The Transferor and the Company agree that the
Purchaser shall be liable for any claims that any such party may have against
the Purchaser only to the extent the Purchaser has Excess Funds (as defined in
that certain Liquidity Agreement, dated as of February 7, 1997, among the
Purchaser, CoreStates, N.A. and the Liquidity Banks parties thereto, relating to
the purchase of the Certificates).

Section 22. Amendments.

            Any provision of this Certificate Purchase Agreement may be amended
or waived if, but only if such amendment or waiver is in writing and is signed
by the Purchaser, the Company and the Transferor and prior written notice is
given to S&P and Moody's; and then such amendment or waiver shall be effective
only in the specific instance and for the specific purpose for which given,
provided that such action will not cause either S&P or Moody's to reduce its
rating of the commercial paper notes issued by the Purchaser.



                                      -14-

<PAGE>   18

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

                                Very truly yours,

                                T&W FUNDING COMPANY I, L.L.C.

                                By: /s/ MICHAEL A. PRICE
                                   -------------------------------------------
                                Name: Michael A. Price
                                      ----------------------------------------
                                Title:  President
                                      ----------------------------------------
                                T&W FINANCIAL CORPORATION




                                By: /s/ MICHAEL A. PRICE
                                   -------------------------------------------
                                Name: Michael A. Price
                                      ----------------------------------------
                                Title:  Chief Executive Officer
                                      ----------------------------------------


The foregoing Agreement is hereby
accepted and entered into as of the
date first written above,


CENTRE SQUARE FUNDING CORPORATION,
     as Purchaser

By: /s/ FRANK BILOTTA
   ---------------------------------

Name:   FRANK BILOTTA
     -------------------------------
       
Title: VICE PRESIDENT
      ------------------------------



<PAGE>   19

                                   SCHEDULE I

                                       to

                         Certificate Purchase Agreement

<TABLE>
<CAPTION>
                                                   Percentage
Purchaser                                           Interest
---------                                          ---------
<S>                                                <C> 

CENTRE SQUARE FUNDING CORPORATION                  100%

</TABLE>

(1)  All payments on account of the Certificates shall be made by bank wire
     transfer of federal or other immediately available funds (identifying each
     payment a T&W Lease Backed Trust 1997-1, Lease Backed Certificates, and the
     due date and application as among principal or interest to each of such
     Certificates) for credit to:

     Bank:               CoreStates Bank, N.A.
     ABA Number:         031000011
     For The Benefit of: Centre Square Funding Corporation - Operating A/C
     Account Number:     14116-03433
     contact:            Cindy Barton (215) 973-4338

(2)  Address for all notices relating to payments and written confirmations of
     such wire transfers and all other communications and notices.

     Centre Square Funding Corporation
     c/o CoreStates Capital Markets Group
     FC 1-8-12-1
     1345 Chestnut Street
     Philadelphia, PA 19101-7618
     Attention: CP Administration

(3)   Taxpayer Identification No.: 13-3865061



                                      -i-