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                                                                   EXHIBIT 10.13

                                AMENDMENT NO. 7
                         TO MASTER REPURCHASE AGREEMENT

                  Amendment No. 7, dated as of May 15, 2003 (this "Amendment"),
between CREDIT SUISSE FIRST BOSTON MORTGAGE CAPITAL LLC (the "Buyer") and OAK
STREET MORTGAGE LLC (formerly known as Cresleigh Financial Services LLC (the
"Seller").

                                    RECITALS

                  The Buyer and the Seller are parties to that certain Master
Repurchase Agreement, dated as of March 1, 2002, as amended by Amendment No. 1,
dated as of May 30, 2002, Amendment No. 2, dated as of September 29, 2002,
Amendment No. 3, dated as of October 30, 2002, Amendment No. 4, dated as of
December 16, 2002, Amendment No. 5, dated as of February 27, 2003 and Amendment
No. 6, dated as of May 1, 2003 (the "Existing Repurchase Agreement"; as amended
by this Amendment, the "Repurchase Agreement"). Capitalized terms used but not
otherwise defined herein shall have the meanings given to them in the Existing
Repurchase Agreement.

                  The Buyer and the Seller have agreed, subject to the terms and
conditions of this Amendment, that the Existing Repurchase Agreement be amended
to reflect certain agreed upon revisions to the terms of the Existing Repurchase
Agreement.

                  Accordingly, the Buyer and the Seller hereby agree, in
consideration of the mutual premises and mutual obligations set forth herein,
that the Existing Repurchase Agreement is hereby amended as follows:

                  SECTION 1. Definitions.

                  (a)      Section 2 of the Existing Repurchase Agreement is
         hereby amended by deleting the definition of "Adjusted Tangible Net
         Worth" in its entirety and replacing it with the following language:

                  ""Adjusted Tangible Net Worth" means, for Seller, (a) the sum
of (i) stockholder equity, (ii) 1% of the outstanding servicing portfolio
balance and (iii) Subordinated Debt (as such term will be mutually agreed upon
by Buyer and Seller), minus (b) the sum of (I) receivables from shareholders,
affiliates or employees (excluding any receivables due from Great Western
Mortgage LLP, for which advances are used exclusively for warehousing
residential mortgage loans) and (II) all intangible assets including capitalized
servicing rights, prepaid assets, goodwill, patents, trade names, trademarks,
copyrights, franchises, any organizational expenses, deferred expenses, and any
other asset as shown as an intangible asset on the balance sheet of the Seller
on a consolidated basis as determined at a particular date in accordance with
GAAP."

                  (b)      Section 2 of the Existing Repurchase Agreement is
         hereby amended by deleting the definition of "Alt A Mortgage Loan" in
         its entirety and replacing it with the following language:





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                  ""Alt A Mortgage Loan" means a first lien Mortgage Loan
originated in accordance with the criteria established by Buyer for Alt-A
Mortgage Loans, as determined by Buyer in its sole discretion and which has a
FICO score of at least 600."

                  (c)      Section 2 of the Existing Repurchase Agreement is
         hereby amended by deleting the definition of "High Cost Mortgage Loan"
         in its entirety and replacing it with the following language:

                  ""High Cost Mortgage Loan" means a Mortgage Loan classified as
(a) a "high cost" loan under the Home Ownership and Equity Protection Act of
1994 or (b) a "high cost," "threshold," "covered," or "predatory" loan under any
other applicable state, federal or local law (or a similarly classified loan
using different terminology under a law imposing heightened regulatory scrutiny
or additional legal liability for residential mortgage loans having high
interest rates, points and/or fees)."

                  (d)      Section 2 of the Existing Repurchase Agreement is
         hereby amended by deleting the definition of "Post Default Rate" in its
         entirety and replacing it with the following language:

                  ""Post Default Rate" means an annual rate of interest equal to
the greater of (a) the Pricing Rate plus 3% or (b) the Mortgage Interest Rate."

                  (e)      Section 2 of the Existing Repurchase Agreement is
         hereby amended by deleting the definition of "Pricing Rate" in its
         entirety and replacing it with the following language:

                  ""Pricing Rate" means LIBOR plus:

                  (a)      1.375% with respect to Transactions the subject of
         which are Conforming Loans (other than Wet-Ink Mortgage Loans);

                  (b)      1.375% with respect to Transactions the subject of
         which are Jumbo Mortgage Loans (other than Wet-Ink Mortgage Loans);

                  (c)      1.375% with respect to Transactions the subject of
         which are Alt A Mortgage Loans (other than Wet-Ink Mortgage Loans);

                  (d)      1.375% with respect to Transactions the subject of
         which are Sub Prime Mortgage Loans (other than Wet-Ink Mortgage Loans);

                  (e)      1.375% with respect to Transactions the subject of
         which are Second Lien Mortgage Loans (other than Wet-Ink Mortgage
         Loans);

                  (f)      1.50% with respect to Transactions the subject of
         which are Wet-Ink Mortgage Loans;

                  (g)      the rate determined in the sole discretion of Buyer
         with respect to Transactions the subject of which are Exception
         Mortgage Loans.

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                  The Pricing Rate shall change in accordance with LIBOR, as
         provided in Section 5(a)."

                  (f)      Section 2 of the Existing Repurchase Agreement is
         hereby amended by deleting the definition of "Termination Date" in its
         entirety and replacing it with the following language:

                  ""Termination Date" means the earlier of (a) April 29, 2004
and (b) the date of the occurrence of an Event of Default."

                  (g)      Section 2 of the Existing Repurchase Agreement is
         hereby amended by deleting the definition of "Test Period" in its
         entirety and replacing it with the following language:

                  ""Test Period" means any calendar quarter."

                  (h)      Section 2 of the Existing Repurchase Agreement is
         hereby amended by deleting the definition of "Wet-Ink Documents" in its
         entirety and replacing it with the following language:

                  ""Wet-Ink Documents" means, with respect to any Wet-Ink
Mortgage Loan, the (a) Transaction Request and (b) the Mortgage Loan Schedule."

                  (i)      Section 2 of the Existing Master Repurchase Agreement
         is hereby amended by adding the following definitions in proper
         alphabetical order:

                  ""BPO" means an opinion of the fair market value of a
Mortgaged Property given by a licensed real estate agent or broker which
generally includes three comparable sales and three comparable listings."

                  ""FICO" means Fair Isaac & Co., or any successor thereto."

                  ""Fidelity Insurance" means insurance coverage with respect to
employee dishonesty, forgery or alteration, theft, disappearance and
destruction, robbery and safe burglary, property (other than money and
securities) and computer fraud in an aggregate amount acceptable to Fannie Mae
and Freddie Mac."

                  ""Mortgage Loan Documents" means the documents in the related
Mortgage File to be delivered to the Custodian."

                  SECTION 2. Margin Maintenance. Section 6(c) of the Existing
Repurchase Agreement is hereby amended by deleting it in its entirety and
replacing it with the following:

                  "(c) In the event that a Margin Deficit exists with respect to
any Purchased Mortgage Loan, Buyer may retain any funds received by it to which
the Seller would otherwise be entitled hereunder, which funds (i) shall be held
by Buyer against the related Margin Deficit and (ii) may be applied by Buyer
against any Purchased Mortgage Loan for which the related Margin Deficit remains
otherwise unsatisfied. Notwithstanding the foregoing, the Buyer retains

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the right, in its sole discretion, to make a Margin Call in accordance with the
provisions of this Section 6."

                  SECTION 3. Representations and Warranties.

                  (a)      Section 13(a) of the Existing Repurchase Agreement is
         hereby amended by adding the following subclauses (26) and (27) at the
         end thereof:

                  "(26) No Reliance. Seller has made its own independent
decisions to enter into the Program Agreements and each Transaction and as to
whether such Transaction is appropriate and proper for it based upon its own
judgment and upon advice from such advisors (including without limitation, legal
counsel and accountants) as it has deemed necessary. Seller is not relying upon
any advice from Buyer as to any aspect of the Transactions, including without
limitation, the legal, accounting or tax treatment of such Transactions.

                  (27) Plan Assets. Seller is not an employee benefit plan as
defined in Section 3 of Title I of ERISA, or a plan described in Section
4975(e)(1) of the Code, and the Purchased Mortgage Loans are not "plan assets"
within the meaning of 29 CFR Section 2510.3-101 in the Seller's hands."

                  (b)      The Seller hereby represents and warrants to the
         Buyer that, as of the Amendment Effective Date, Seller's Adjusted
         Tangible Net Worth is not less than $8 Million.

                  SECTION 4. Covenants.

                  (a)      Section 14(a) of the Existing Repurchase Agreement is
         hereby amended by deleting it in its entirety and replacing it with the
         following:

                  "(a)     Adjusted Tangible Net Worth. Seller shall maintain an
Adjusted Tangible Net Worth of at least $8 million."

                  (b)      Section 14(b) of the Existing Repurchase Agreement is
         hereby amended by deleting it in its entirety and replacing it with the
         following:

                  "(b)     Indebtedness to Adjusted Tangible Net Worth Ratio.
Seller's ratio (i) of the sum (without duplication) of the Seller's Indebtedness
and the aggregate outstanding Purchase Price of the Purchased Mortgage Loans
under this Agreement to (ii) Adjusted Tangible Net Worth shall not exceed 20:1."

                  (c)      Section 14 of the Existing Repurchase Agreement is
         hereby amended by adding the following clauses (ff) and (gg) at the
         end thereof:

                  "(ff) Plan Assets. Seller shall not be an employee benefit
plan as defined in Section 3 of Title I of ERISA, or a plan described in Section
4975(e)(1) of the Code and the Seller shall not use "plan assets" within the
meaning of 29 CFR Section 2510.3-101 to engage in this Repurchase Agreement or
any Transaction hereunder.

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                  (gg) Minimum Current Ratio. Seller's ratio of "total assets"
to "total liabilities" (each as determined in accordance with GAAP) shall not
fall below 1:1."

                  SECTION 5. Events of Default. Section 15(g) of the Existing
Master Repurchase Agreement is hereby amended by deleting it in its entirety and
replacing it with the following:

                  "(g) Breach of Financial Representation or Covenant or
Obligation. A breach by Seller of any of the representations, warranties or
covenants or obligations set forth in Sections 13(a)(1), 13(a)(7), 13(a)(12),
13(a)(19), 13(a)(24), 14a, 14b, 14d, 14e, 14r, 14v, 14w, 14bb, 14cc, 14dd, 14ee,
14ff or 14gg of this Agreement.

                  SECTION 6. Remedies Upon Default.

                  (a)      Section 16(d) of the Existing Master Repurchase
         Agreement is hereby amended by deleting it in its entirety and
         replacing it with the following:

                  "(d)     Buyer shall have the right to direct all servicers
then servicing any Purchased Mortgage Loans to remit all collections thereon to
Buyer, and if any such payments are received by Seller, Seller shall not
commingle the amounts received with other funds of Seller and shall promptly pay
them over to Buyer. Buyer shall also have the right to terminate any one or all
of the servicers then servicing any Purchased Mortgage Loans with or without
cause. In addition, Buyer shall have the right to immediately sell the Purchased
Mortgage Loans and liquidate all Repurchase Assets. Such disposition of
Purchased Mortgage Loans may be, at Buyer's option, on either a
servicing-released or a servicing-retained basis. Buyer shall be entitled to
place the Purchased Mortgage Loans in a pool for issuance of mortgage-backed
securities at the then-prevailing price for such securities and to sell such
securities for such prevailing price in the open market. Buyer shall also be
entitled to sell any or all of such Mortgage Loans individually for the
prevailing price. Buyer shall also be entitled, in its sole discretion to elect,
in lieu of selling all or a portion of such Purchased Mortgage Loans, to give
the Seller credit for such Purchased Mortgage Loans and the Repurchase Assets in
an amount equal to the Market Value of the Purchased Mortgage Loans against the
aggregate unpaid Repurchase Price and any other amounts owing by the Seller
hereunder."

                  (b)      Section 16(j) of the Existing Master Repurchase
         Agreement is hereby amended by deleting it in its entirety and
         replacing it with the following:

                  "(j)     Buyer may enforce its rights and remedies hereunder
without prior judicial process or hearing, and Seller hereby expressly waives
any defenses Seller might otherwise have to require Buyer to enforce its rights
by judicial process. Seller also waives any defense (other than a defense of
payment or performance) Seller might otherwise have arising from the use of
nonjudicial process, enforcement and sale of all or any portion of the
Repurchase Assets, or from any other election of remedies. Seller recognizes
that nonjudicial remedies are consistent with the usages of the trade, are
responsive to commercial necessity and are the result of a bargain at arm's
length."

                  SECTION 7. Reports. Section 17(a)(7) of the Existing Master
Repurchase Agreement is hereby amended by adding the following subclause (h) at
the end thereof:

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                  "(h) any material change in the Indebtedness of the Seller,
including, without limitation, any default, renewal, non-renewal, termination,
increase in available amount or decrease in available amount related thereto."

                  SECTION 8. Power of Attorney. Section 28 of the Existing
Master Repurchase Agreement is hereby amended by deleting it in its entirety and
replacing it with the following:

                  "Seller hereby authorizes Buyer to file such financing
statement or statements relating to the Repurchase Assets without Seller's
signature thereon as Buyer, at its option, may deem appropriate. Seller hereby
appoints Buyer as Seller's agent and attorney-in-fact to execute any such
financing statement or statements in Seller's name and to perform all other acts
which Buyer deems appropriate to perfect and continue its ownership interest in
and/or the security interest granted hereby, if applicable, and to protect,
preserve and realize upon the Repurchase Assets, including, but not limited to,
the right to endorse notes, complete blanks in documents, transfer servicing,
and sign assignments on behalf of Seller as its agent and attorney-in-fact. This
agency and power of attorney is coupled with an interest and is irrevocable
without Buyer's consent. Notwithstanding the foregoing, the power of attorney
hereby granted may be exercised only during the occurrence and continuance of
any Event of Default hereunder. Seller shall pay the filing costs for any
financing statement or statements prepared pursuant to this Section 28."

                  SECTION 9. Confidentiality. Section 32 of the Existing
Repurchase Agreement is hereby amended by adding the following sentence at the
end thereof:

                  "Notwithstanding the foregoing or anything to the contrary
contained herein or in any other Program Agreement, the parties hereto may
disclose to any and all Persons, without limitation of any kind, the federal
income tax treatment of the Transactions, any fact relevant to understanding the
federal tax treatment of the Transactions, and all materials of any kind
(including opinions or other tax analyses) relating to such federal income tax
treatment; provided that Seller may not disclose the name of or identifying
information with respect to Buyer or Agent or any pricing terms (including,
without limitation, the Pricing Rate, Purchase Price Percentage and Purchase
Price) or other nonpublic business or financial information (including any
sublimits and financial covenants) that is unrelated to the purported or claimed
federal income tax treatment of the Transactions and is not relevant to
understanding the purported or claimed federal income tax treatment of the
Transactions, without the prior written consent of the Buyer."

                  SECTION 10. Authorizations. The Existing Master Repurchase
Agreement is hereby amended by adding the following Section 37 thereto:

                  "37. AUTHORIZATIONS

                  Any of the persons whose signatures and titles appear on
Schedule 2 are authorized, acting singly, to act for Seller or Buyer, as the
case may be, under this Agreement."

                  SECTION 11. Schedules.

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                  (a)      Representation and Warranty (yy) in Schedule 1 of the
         Existing Repurchase Agreement is hereby amended by deleting it in its
         entirety and replacing it with the following:

                  "(yy)    Predatory Lending Regulations; High Cost Loans. None
of the Mortgage Loans are classified as High Cost Mortgage Loans."

                  (b)      The Existing Master Repurchase Agreement is hereby
         amended by adding Schedule 1 of this Amendment as Schedule 2 to the
         Existing Master Repurchase Agreement.

                  SECTION 12. Conditions Precedent. This Amendment shall become
effective on May 15, 2003 (the "Amendment Effective Date"), subject to the
satisfaction of the following conditions precedent:

                  12.1 Delivered Documents. On the Amendment Effective Date, the
Buyer shall have received the following documents, each of which shall be
satisfactory to the Buyer in form and substance:

                  (a) this Amendment, executed and delivered by a duly
         authorized officer of the Buyer and the Seller;

                  (b) evidence that the Seller has added the Buyer as loss payee
         under the Seller's Fidelity Insurance; and

                  (c) such other documents as the Buyer or counsel to the Buyer
         may reasonably request.

                  SECTION 13. Representations and Warranties. The Seller hereby
represents and warrants to the Buyer that it is in compliance with all the terms
and provisions set forth in the Repurchase Agreement on its part to be observed
or performed, and that no Event of Default has occurred or is continuing, and
hereby confirm and reaffirm the representations and warranties contained in
Section 13 of the Repurchase Agreement.

                  SECTION 14. Limited Effect. Except as expressly amended and
modified by this Amendment, the Existing Repurchase Agreement shall continue to
be, and shall remain, in full force and effect in accordance with its terms.

                  SECTION 15. Counterparts. This Amendment may be executed by
each of the parties hereto on any number of separate counterparts, each of which
shall be an original and all of which taken together shall constitute one and
the same instrument.

                  SECTION 16. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED
BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK WITHOUT
REFERENCE TO THE CHOICE OF LAW PROVISIONS THEREOF.

                            [SIGNATURE PAGE FOLLOWS]

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                  IN WITNESS WHEREOF, the parties have caused their names to be
signed hereto by their respective officers thereunto duly authorized as of the
day and year first above written.

Buyer:

                                CREDIT SUISSE FIRST BOSTON MORTGAGE CAPITAL LLC,
                                as Buyer

                                By: /s/ Jeffrey A. Detwiler
                                    --------------------------------------------
                                    Name: Jeffrey A. Detwiler
                                    Title: Managing Director

Seller:

                                OAK STREET MORTGAGE LLC
                                as Seller

                                By: /s/ Craig L. Royal
                                    --------------------------------------------
                                    Name: Craig L. Royal
                                    Title: Chief Financial Officer

<PAGE>

                          SCHEDULE 1 TO AMENDMENT NO. 7

                                   SCHEDULE 2
                           AUTHORIZED REPRESENTATIVES

SELLER NOTICES

                                          Address:
Name:
Telephone:
Facsimile:

SELLER AUTHORIZATIONS

Any of the persons whose signatures and titles appear below are authorized,
acting singly, to act for Seller under this Agreement:

<TABLE>
<CAPTION>
           Name                       Title                    Signature
-------------------------    -----------------------   ------------------------
<S>                          <C>                       <C>
</TABLE>

                                   Schedule 1