Exhibit 10.3

EXECUTION VERSION

AMENDMENT NO. 4
TO AMENDED AND RESTATED MASTER REPURCHASE AGREEMENT

Amendment No. 4, dated as of May 31, 2007 (this “Amendment”) is entered into by
and among FIELDSTONE MORTGAGE COMPANY, a Maryland corporation (“FMC” and a
“Seller”), FIELDSTONE INVESTMENT CORPORATION, a Maryland corporation (“FIC” and
a “Seller” and, together with FMC, the “Sellers”), and MERRILL LYNCH BANK USA, a
Utah industrial loan corporation (the “Buyer”).

RECITALS

The Buyer and the Sellers are parties to that certain Amended and Restated
Master Repurchase Agreement, dated as of October 31, 2006, as amended by
Amendment No. 1, dated as of December 29, 2006, Amendment No. 2, dated as of
March 30, 2007 and Amendment No. 3, dated as of April 18, 2007 (as the same may
have been amended and supplemented from time to time, the “Existing Repurchase
Agreement” and 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 Sellers 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 Sellers 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. Waiver. For purposes of this Amendment, this Section 2 will be
effective only for the period from and including May 1, 2007 through and
including June 30, 2007 (the “Waiver Period”).

1.1 Covenants. Section 12(k) of the Existing Repurchase Agreement is hereby
temporarily amended by deleting clauses (i) and (ii) thereto in their entirety
and replacing them with the following language:

“(i) Maintenance of Adjusted Tangible Net Worth. FIC shall maintain a Adjusted
Tangible Net Worth of not less than $250,000,000.”

“(ii) Maintenance of Ratio of Indebtedness to Adjusted Tangible Net Worth. FIC
shall maintain the ratio of Indebtedness to Adjusted Tangible Net Worth no
greater than 20:1.”

SECTION 2. Conditions Precedent. This Amendment shall become effective on May 1,
2007 (the “Amendment Effective Date”) subject to the satisfaction of the
following conditions precedent:

2.1 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 and duly authorized officers of the
Buyer and the Sellers; and

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

SECTION 3. 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. Other than as
expressly set forth herein, the execution of this Amendment by the Buyer shall
not operate as a waiver of any of its rights, powers or privileges under the
Repurchase Agreement or any other Repurchase Document, including without
limitation, any rights, powers or privileges relating to other existing or
future breaches of, or Defaults or Events of Default under, the Repurchase
Agreement or any other Repurchase Document (whether the same or of a similar
nature as the breaches identified herein or otherwise) except as expressly set
forth herein.

SECTION 4. Fees. The Sellers agree to pay as and when billed by the Buyer all of
the reasonable fees, disbursements and expenses of counsel to the Buyer in
connection with the development, preparation and execution of, this Amendment or
any other documents prepared in connection herewith and receipt of payment
thereof shall be a condition precedent to the Buyer entering into any
Transaction pursuant hereto.

SECTION 5. Confidentiality. The parties hereto acknowledge that this Amendment,
the Existing Repurchase Agreement, and all drafts thereof, documents relating
thereto and transactions contemplated thereby are confidential in nature and the
Seller agree that, unless otherwise directed by a court of competent
jurisdiction or as is necessary to do so in working with governmental agencies
or regulatory bodies in order to comply with any applicable federal or state
laws, they shall limit the distribution of such documents and the discussion of
such transactions to such of its officers, employees, attorneys, accountants and
agents as is required in order to fulfill its obligations under such documents
and with respect to such transactions.

SECTION 6. GOVERNING LAW. THIS AMENDMENT 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 SUCH LAWS.

SECTION 7. Counterparts. This Amendment may be executed in one or more
counterparts and by different parties hereto on separate counterparts, each of
which, when so executed, shall constitute one and the same agreement.

SECTION 8. Conflicts. The parties hereto agree that in the event there is any
conflict between the terms of this Amendment, and the terms of the Existing
Repurchase Agreement, the provisions of this Amendment shall control.

[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: MERRILL LYNCH BANK USA, as Buyer

By: /s/ Joseph Magnus
Name: Joseph Magnus
Title: Director

Seller: FIELDSTONE INVESTMENT CORPORATION, as Seller

By: /s/ Mark C. Krebs
Name: Mark C. Krebs
Title: Sr. Vice President & Treasurer

Seller: FIELDSTONE MORTGAGE COMPANY, as Seller

By: /s/ Mark C. Krebs
Name: Mark C. Krebs
Title: Sr. Vice President & Treasurer

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