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                                                                   Exhibit 10.21


                                 PROMISSORY NOTE


$200,000                                                           March 7, 2000

         For value received, CONSTRUCTION PORTFOLIO FUNDING, INC. (the "MAKER"),
a Texas corporation, promises to pay to the order of ALAN FERREE (the "HOLDER")
the principal amount of Two Hundred Thousand Dollars ($200,000) in accordance
with the terms of this Note.

         1. Payment of Principal. The principal of this Note shall be payable in
full on April 30, 2000.

         2. Interest. The unpaid principal of this Note outstanding from time to
time shall bear interest, beginning as of the date hereof, at an annual rate of
fourteen percent (14%), computed on the basis of a 365-day year and continuing
until the principal hereof is repaid in full. Interest shall be payable in
arrears on the last day of each calendar month.

         3. Prepayments. The Maker may prepay this Note in whole or, from time
to time, in part without penalty or premium. All such prepayments shall be
applied against the required installments of principal in order of maturity
thereof.

         4. Place of Payments. All payments of principal and interest under this
Note shall be made to the order of Holder at the address specified in numbered
paragraph 12 hereof.

         5. Default; Acceleration. Maker agrees that, in the event that:

         (i) any installment of principal or interest under this Note shall not
         be paid when it is due and payable, and such failure to pay is not
         cured within fifteen (15) days after notice from Holder of such failure
         to pay; or

         (ii) Maker shall suffer or permit the filing by or against the Maker of
         any petition for adjudication, arrangement, reorganization or the like
         under any bankruptcy or insolvency law (and, in the case of an
         involuntary proceeding the same is not dismissed within 30 days), make
         an assignment for the benefit of creditors or suffer or permit the
         appointment of a receiver for any part of Maker's property,

then, upon the happening of any such event (each an "Event of Default"), the
entire indebtedness and accrued interest thereon due under this Note shall, at
the option of the Holder, accelerate and become immediately due and payable
without notice.

         6. Cost of Collection. The Maker shall reimburse the Holder for all
reasonable costs and expenses, including reasonable attorneys' fees, which may
be incurred by the Holder in collecting any amounts due hereunder.

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         7. Loss, Theft, Destruction or Mutilation of Note. Upon receipt by the
Maker of evidence reasonably satisfactory to the Maker of the loss, theft,
destruction or mutilation of this Note, and of indemnity or security reasonably
satisfactory to the Maker, and upon reimbursement to the Maker of all reasonable
expenses incidental thereto, and upon surrender and cancellation of this Note,
if mutilated, the Maker will make and deliver a new note of like tenor in lieu
of this Note. Any note made and delivered in accordance with the provision of
this paragraph shall be dated as of the date to which interest has been paid on
this Note, or if no interest has theretofore been paid on this Note, then dated
the date hereof.

         8. Governing Law. This Note shall be construed in accordance with and
governed by the laws of the State of Texas, without regard to principles of
conflicts of laws.

         9. Successors and Assigns. All the covenants, stipulations, promises
and agreements contained in this Note by or on behalf of the Maker or the Holder
and all rights of the Maker or the Holder contained in this Note shall bind or
inure to their respective successors, assigns, heirs and personal
representatives, whether so expressed or not.

         10. Cumulative Remedies. No course of dealing, or any delay or omission
of the Holder to exercise any right or power hereunder (including, without
limitation, any right or power arising from any default or failure of
performance of the Maker), shall exhaust, impair, waive or otherwise prejudice
any such right or power or prevent its exercise. Every right and remedy given to
the Holder hereunder, by any and all agreements executed and delivered in
connection herewith or by law may be exercised from time to time as often as the
Holder may deem expedient. No waiver by the Holder of any such default, whether
such waiver be full or partial, shall extend to or be taken to affect any
subsequent default, or to impair the rights resulting therefrom except as may be
otherwise expressly provided herein. No remedy hereunder is intended to be
exclusive of any other remedy but each and every remedy shall be cumulative and
in addition to any and every other remedy given hereunder or otherwise existing.

         11. Headings. The headings of the paragraphs of this Note are inserted
for convenience only and shall not be deemed to constitute a part hereof.

         12. Notices. All notices, requests, demands and other communications
hereunder must be in writing and shall be deemed to have been duly given if
delivered by hand or mailed by first class, registered or certified mail, return
receipt requested, postage and registry fees prepaid, and addressed as follows:


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          (a)      If to Maker:           Construction Portfolio Funding, Inc.
                                          NAB Asset Corporation
                                          4144 N. Central Expressway, Suite 900
                                          Dallas, TX 75204
                                          Attention: Alan Ferree
                                          Telephone: (214) 860-1882
                                          Telecopy: (214) 821-3689

          (b)      If to Holder:          Alan Ferree
                                          c/o NAB Asset Corporation
                                          4144 N. Central Expressway, Suite 900
                                          Dallas, TX 75204
                                          Telephone: (214) 860-1882
                                          Telecopy: (214) 821-3689

Any of the foregoing parties by notice in writing mailed to the other parties
may change the name and address to which notices, requests, demands and other
communications to it or him shall be mailed.

         13. Consideration. This Note evidences the following indebtedness of
the Maker to the Holder: a loan in the amount hereof made by the Holder to the
Maker on the date hereof.

         IN WITNESS WHEREOF, the Maker has signed this Note by a duly authorized
officer and dated it as of the day and year first above written.

                                            CONSTRUCTION PORTFOLIO FUNDING, INC.


                                            By: /s/ James E. Hinton
                                            Name: James E. Hinton
                                            Title: President



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