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                                                                    Exhibit 10.7

         THIS FOURTH AMENDMENT TO WAREHOUSE LOAN AND SECURITY AGREEMENT (this
"Amendment") is made as of February 1, 2000 among NHELP-I, INC., a corporation
duly organized under the laws of the State of Nevada (the "Borrower"), CONCORD
MINUTEMEN CAPITAL COMPANY, LLC, a Delaware limited liability company
("Concord"), and NORWEST BANK MINNESOTA, NATIONAL ASSOCIATION, a national
banking association, as eligible lender and trustee (the "Trustee").

                             PRELIMINARY STATEMENTS

         1.       The Borrower, Concord and the Trustee have previously entered
into that certain Warehouse Loan and Security Agreement dated as of September
30, 1998 (as heretofore amended by that First Amendment to Warehouse Loan and
Security Agreement dated as of December 15, 1998, that Second Amendment to
Warehouse Loan and Security Agreement dated as of September 29, 1999 and that
Third Amendment to Warehouse Loan and Security Agreement dated as of November
16, 1999, the "Original Agreement").

         2.       Pursuant to Section 9.01 of the Original Agreement, the
Borrower, the Required Lenders and, to the extent affected thereby, the Trustee
may amend the Original Agreement with the prior written consent of the Agent. As
of this date, Concord is the Required Lender and the Agent has given its written
consent to the execution of this Amendment.

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

                                    ARTICLE I

                        AMENDMENTS TO ORIGINAL AGREEMENT

         All words and phrases defined in Article I of the Original Agreement
shall have the same meaning in this Amendment, except as otherwise appears in
this Article.

         SECTION 1.01. DEFINITIONS. The definition of "Facility Limit" set forth
in the Original Agreement is deleted in its entirety and the following inserted
therefor:

                           "Facility Limit" means, at any time, $465,000,000 as
         such amount may be adjusted from time to time pursuant to Section 2.03;
         provided, however, at all times on or after the termination of the
         Revolving Period, the "Facility Limit" shall mean the Facility Amount.

                                   ARTICLE II

                               GENERAL PROVISIONS

         SECTION 2.01 DATE OF EXECUTION. Although this Amendment for convenience
and for the purpose of reference is dated as of the date first written above and
shall be effective as of March 1, 2000, the actual dates of execution by the
Borrower, by Concord and by the Trustee are as indicated by their respective
acknowledgments hereto annexed.

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         SECTION 2.02 LAWS GOVERNING. It is the intent of the parties hereto
that this Amendment shall in all respects be governed by the internal law, and
not the conflicts, of the State of Illinois.

         SECTION 2.03 SEVERABILITY. If any covenant, agreement, waiver or part
thereof contained in this Amendment shall be forbidden by any pertinent law or
under any pertinent law shall be effective to render this Amendment invalid or
unenforceable or to impair the lien hereof, then such covenant, agreement,
waiver, or part thereof shall itself be and is hereby declared to be wholly
ineffective, and this Amendment shall be construed as if the same were not
included therein.

         SECTION 2.04 COUNTERPARTS. This Amendment may be executed in one or
more counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument. One or more counterparts
of this Amendment may be delivered by telecopier, with the intention that they
shall have the same effect as an original counterpart thereof.

                                   ARTICLE III

                      APPLICABILITY OF ORIGINAL AGREEMENT

         The provisions of the Original Agreement are hereby ratified, approved
and confirmed, except as otherwise expressly modified by this Amendment. The
representations, warranties and covenants contained in the Original Agreement,
except as expressly modified herein, are hereby reaffirmed with the same force
and effect as if fully set forth herein and made again as of the date hereof.

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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their respective officers thereunto duly authorized, as of the date
first written above.

                               THE BORROWER:

                               NHELP-I, INC.

                               By /s/ Terry Heimes
                                  -------------------------------
                               Title: Vice President
                               Date:

                               THE LENDER:

                               CONCORD MINUTEMEN CAPITAL COMPANY, LLC

                               By /s/ Thomas Irvin
                                  -------------------------------
                               Title: Manager
                               Date:  February 1, 2000

                               THE TRUSTEE:

                               NORWEST BANK MINNESOTA, NATIONAL ASSOCIATION

                               By /s/ Susan E. Jacobsen
                                  -------------------------------
                               Title: Corporate Trust Officer
                               Date:  2/1/00

CONSENTED TO AND ACKNOWLEDGED:

THE AGENT:

MELLON BANK, N.A., as Agent

By /s/ R. F. Wagner
   ----------------------------
Title: VICE PRESIDENT
Date:  FEBRUARY 23, 2000

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