
<PAGE>   1
                                                                  EXHIBIT 10(k)


        [NORWEST BANK LOGO                    Norwest Bank Arizona, N.A.
                                              Commercial Real Estate Department
                                              3300 North Central Avenue
                                              Mail Station 9008
                                              Phoenix, Arizona 85012
                                              602/263-7228
                                              Fax: 602/248-3667


August 28, 1996

Monterey Management Tucson, Inc.
Monterey Homes Tucson Corporation
Monterey Management, Inc.
Monterey Homes Corporation
6613 North Scottsdale Road, Suite #200 
Scottsdale, Arizona 85250

RE:     Letter Loan Agreement

Gentlemen:

We are pleased to inform you that Norwest Bank Arizona, National Association
(the "Bank"), has approved the Credit Facility described below, according to the
terms and conditions set out in this Letter Loan Agreement (the "Agreement"), in
addition to those set out in any other documents (collectively, the "Loan
Documents") which may be signed in connection with this transaction.

         BORROWERS: For purposes of this Agreement, "Borrowers" shall mean,
         collectively, Monterey Management Tucson, Inc., Monterey Homes Tucson
         Corporation, Monterey Management, Inc. and Monterey Homes Corporation
         (the "Borrowers").

         GUARANTORS: For purposes of this Agreement, "Guarantors" shall mean,
         jointly and severally, Bill Cleverly, Steve Hilton and Benee Hilton
         (the "Guarantors").

         CREDIT FACILITY: Borrowers agree to borrow from the Bank, and, subject
         to the terms and conditions of this Agreement and the other Loan
         Documents, Bank agrees to loan, to or for the benefit of Borrowers, a
         sum not to exceed Seven Million Five Hundred Thousand and no/100ths
         Dollars ($7,500,000.00). Indebtedness arising under the Credit Facility
         shall be evidenced by and bear interest as provided in Bank's form of
         promissory note, dated August 28, 1996 (the "Note"), which shall be
         duly signed and delivered to Bank by Borrower, and all notes taken in
         renewal or modification of, additional to or substitution for it.

         LOAN FEE: Borrowers shall pay to the Bank upon acceptance of this
         Agreement a fee equal to three-quarters of one percent (3/4%) of the
         funded amount under the Credit Facility (the "Loan Fee"), which fee
         shall be deemed fully earned by the Bank and non-refundable to
         Borrowers.

         LOAN PURPOSE: The purpose of the Credit Facility is to partially fund
         distributions of Borrowers' Previously Taxed Earnings and 1996
         subchapter S tax liabilities to Bill Cleverly and Steve Hilton prior to
         the merger of Borrowers with Homeplex Mortgage Investments Corporation
         ("Homeplex").

         MATURITY DATE: The Maturity Date of the Credit Facility is August 28,
         1997.
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         INTEREST RATE: Interest on the Credit Facility shall be calculated at
         an annual rate equal to one-half of one percent (1/2%) in excess of the
         Base Rate on the basis of actual days elapsed in a year of 360 days.
         "Base Rate" means the rate established by the Bank from time to time as
         its "base" or " prime" rate of interest. The interest rate may vary as
         often as daily with any change in the Base Rate.


         REPAYMENT: The Credit Facility shall be repaid in successive monthly
         installments of principal in the amount of $500,000.00 each, plus
         interest, commencing on October 15, 1996, and continuing on the last
         day of each succeeding month until the Maturity Date, at which time the
         entire remaining balance of principal and interest shall be immediately
         due and payable. In addition, Borrowers shall make an additional
         principal reduction in the three month period ending May 31, 1997, in
         an amount of not less than $750,000.00.

         COLLATERAL: The Credit Facility shall be unsecured, however, Guarantors
         shall each, jointly and severally, guarantee repayment of all
         indebtedness arising under this Agreement. In addition, Bill Cleverly
         and Steve Hilton shall each pledge to Bank, to secure the respective
         guaranty of each, short-term U.S. Government Treasury instruments or
         blue chip or investment grade marketable securities in an amount of
         $3,750,000.00 or 50% of the maximum funded advances, whichever is less.
         The total value of these collateral securities owned, respectively by
         Bill Cleverly and Steve Hilton, shall be included as liquidity for the
         purposes of calculating the personal liquidity as described in
         Significant Covenants section xi.

         PREPAYMENT: The Credit Facility may be prepaid in whole or in part at
         any time upon written or telephonic notice to the Bank. Prepayment must
         be received by the Bank before 12:00 p.m. local time in Arizona on any
         business day in order for prepayment to be credited as of that business
         day. Prepayment received at 12:00 p.m. or later local time in Arizona
         on any business day will be credited as of the next business day.

         SIGNIFICANT COVENANTS: Not in limitation of any other covenants which
         may be required by the Bank pursuant to the Loan Documents, during the
         term of the Credit Facility or so long as any portion of it is
         outstanding, Borrowers shall:

         i.    provide signed copies of each Guarantor's filed state and federal
               income tax returns with all schedules and attachments within 120
               days after calendar year end, or when filed, if filed later;
         ii.   provide a resolution from each Borrower authorizing the 
               execution, delivery and performance of all of the Loan Documents
               by such Borrower and all acts and transactions   required or
               contemplated by them;
        
         iii.  provide quarterly company-prepared consolidated financial
               statements including each Borrower 30 days after each calendar
               month end;
         iv.   provide annual personal financial statements for each Guarantor
               within 30 days after each calendar year end;
         v.    provide CPA-audited annual consolidated financial statements
               including each Borrower within 90 days after each fiscal year 
               end;
         vi.   not make any loans to others;
         vii.  not incur any obligations except for those incurred in the
               ordinary course of its business;
         viii. maintain a liquidity, measured quarterly, of not less than
               $500,000.00;
         ix.   not request Advances under the Credit Facility for the purpose of
               purchasing fixed assets or the making of investments;
         x.    maintain principal bank accounts with the Bank;
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         xi.  cause each of Bill Cleverly and Steve Hilton to maintain, at all
              times, personal liquidity of not less than 50% of the outstanding
              balance of the Credit Facility; and

         xii. pay all taxes when due.



         EXPENSES: Expenses, not limited to internal or external legal fees, an
         appraisal fee and an environmental assessment fee plus all costs
         incurred in connection with documenting, maintaining, and enforcing the
         Credit Facility, including, but not limited to, court costs and
         attorney fees, shall be paid by the Borrowers.

         CONDITIONS TO FACILITY: The Bank's obligation to provide or to fund all
         or any portion of the Credit Facility and the extension of credit, if
         any, set forth in the Loan Documents will be conditioned upon the
         following:

         i.   no material adverse change in the condition, financial or
              otherwise, of Borrowers or Guarantors shall have occurred, and no
              action, suit or proceeding shall be instituted or threatened
              relating to the Credit Facility;
         ii.  execution of and delivery to the Bank of the Loan Documents, all
              in form and substance satisfactory to the Bank and its counsel;

         iii. Borrowers shall hold harmless and indemnify the Bank from any and
              all claims of any nature arising out of Borrowers' business;
         iv.  Borrowers shall not be in default of any of the terms of the
              Credit Facility, any of the Loan Documents or of any other
              agreement with the Bank;
         v    Borrowers shall have received the consents and waivers of the
              holders of Borrowers' 13% Senior Subordinated Notes due 2001 (the
              "Senior Notes") and Warrantholders described in that certain
              Consent Solicitation Statement, dated August 7, 1996 and that
              certain undated Notice to Warrantholders;
         vi.  Borrowers shall not be in default of any of the terms of the
              Senior Notes or any other loan agreement, indenture or material
              contract to which Borrowers, Guarantors or any of them are parties
              or by which they are bound;

         REPRESENTATIONS AND WARRANTIES:

         i.   Borrowers jointly and severally represent and warrant to the Bank
              that this Agreement, the Loan Documents and the Credit Facility
              are, on the date of funding, and will be, following the Monterey
              Transactions and the Merger (as such terms are defined in that
              certain Agreement and Plan of Reorganization with Homeplex in the
              form previously provided by the Borrowers to the Bank), valid and
              binding obligations of the Borrowers, enforceable against them in
              accordance with their terms.

         ii.  Guarantors jointly and severally represent and warrant to the Bank
              that the Guarantee provided by this Agreement, the Loan Documents
              and Credit Facility is, on the date of funding, and will be,
              following the Monterey Transactions and the Merger (as such terms
              are defined in that certain Agreement and Plan of Reorganization
              with Homeplex in the form previously provided by the Borrowers to
              the Bank), a valid and binding obligation of each Guarantor,
              enforceable against him in accordance with the terms of such
              Guarantee.

         iii. Borrowers and Guarantors jointly and severally represent and
              warrant to the Bank that the representations and warranties of
              each of them made in that certain Amended and Restated Loan
              Agreement, dated as of August 8, 1995, as amended and in effect on
              the date hereof, are true and correct and are incorporated by
              reference into this Agreement as if fully set forth herein.
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         EVENTS OF DEFAULT: Each of the following shall constitute an Event of
         Default:

         i.   default in any payment of interest or of principal on the Note
              when due, and continuance thereof for 10 days;
         ii.  default in the observance or performance of any agreement of any
              Borrower set forth in the Significant Covenants or Conditions to
              Facility hereof or in any other agreement between the Bank and the
              Borrower or evidence of indebtedness of any Borrower to the Bank;
         iii. default in the observance or performance of any other agreement of
              any Borrower herein set forth and continuance thereof for 30 days;
         iv.  default by any Borrower or any Guarantor in the payment of any
              other indebtedness for borrowed money to any party or in the
              observance or performance of any term, covenant or agreement of
              any Borrower or any Guarantor in any agreement relating to any
              indebtedness to any party, the effect of which default is to
              permit the holder of such indebtedness to declare the same due
              prior to the date fixed for its payments under the terms thereof,
         v.   any representation or warranty made by Borrowers herein or in any
              statement or certificate furnished by the Borrowers hereunder, is
              untrue in any material respect; or
         vi.  the occurrence of any litigation or governmental proceeding which
              is pending or threatened against any Borrower or any Guarantor,
              which could have a material adverse effect on the Borrower's or
              Guarantor's financial condition or business, and which is not
              remedied within a reasonable period of time (a reasonable period
              of time not to exceed 10 days) after notice thereof to the
              Borrowers.

         REMEDIES: Immediately upon the occurrence of an Event of Default, or at
         any time thereafter, unless such Event of Default is remedied, the Bank
         or the holder of the Note may, by notice in writing to the Borrower,
         declare the Credit Facility to be terminated or the Note to be due and
         payable, or both, whereupon the Credit Facility shall immediately
         terminate or the Note shall immediately become due and payable, or
         both, as the case may be.

         BANKRUPTCY: If any Borrower or any Guarantor becomes insolvent or
         bankrupt, or makes an appointment for the benefit of creditors or
         consents to the appointment of a custodian, trustee or receiver for
         itself or for the greater part of its properties; or a custodian,
         trustee or receiver is appointed for the Borrower or any Guarantor or
         for the greater part of its properties without its consent and is not
         discharged within 60 days; or bankruptcy, reorganization or liquidation
         proceedings are instituted by or against the Borrower or any Guarantor
         and, if instituted against it, are consented to by it or remain
         undismissed for 60 days, or if any Guarantor shall die, then the Credit
         Facility shall immediately terminate and the Note shall automatically
         become immediately due and payable, without notice.

         MISCELLANEOUS:

         (i)  Collateral securing the Credit Facility shall also secure any
              other indebtedness of the Borrower to the Bank, and collateral
              securing any other indebtedness of the Borrower to the Bank shall
              also secure the Credit Facility.

         ARBITRATION: Subject to the provisions of the next paragraph below, the
         Bank, the Borrowers and the Guarantors agree to submit to binding
         arbitration any and all claims, disputes and controversies
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         between or among them, whether or in tort, contract or otherwise (and
         their respective employees, officers, directors, attorneys and other
         agents) arising out of or relating to in any way (i) the Credit
         Facility and related loan and security documents which are the subject
         of this Agreement and its negotiation, execution, collateralization,
         administration, repayment, modification, extension, substitution,
         formation, inducement, enforcement, default or termination; or (ii)
         requests for additional credit. However, "Core Proceedings" under the
         United States Bankruptcy Code shall be exempted from arbitration. Such
         arbitration shall proceed in Phoenix, Arizona, shall be governed by the
         Federal Arbitration Rules of the American Arbitration Association
         ("AAA"). The arbitrator shall give effect to statutes of limitation in
         determining any claim. Any controversy concerning whether an issue is
         arbitrable shall be determined by the arbitrator. Judgment upon the
         award rendered by the arbitrator may be entered in any court having
         jurisdiction.

         Nothing in the preceding paragraph, nor the exercise of any right to
         arbitrate, shall limit the right of any party hereto (i) to foreclose
         against real or personal property collateral by the exercise of the
         power of sale, under a deed of trust, mortgage, or other pledge,
         security agreement or instrument, or applicable law; (ii) to exercise
         self-help remedies relating to collateral or proceeds of collateral
         such as setoff or repossession; or (iii) to obtain provisional or
         ancillary remedies such as replevin, injunctive relief, attachment or
         appointment of a receiver from a court having jurisdiction, before,
         during or after the pendency of any arbitration proceeding. The
         institution and maintenance of any action for such judicial relief, or
         pursuit of provisional or ancillary remedies, or exercise of self-help
         remedies shall not constitute a waiver of the right or obligation of
         any party to submit any claim or dispute to arbitration, including
         those claims or disputes arising from exercise of any such judicial
         relief, or provisional or ancillary remedies, or exercise of self-help
         remedies.

         Arbitration under this Agreement shall be before a single arbitrator,
         who shall be a neutral attorney who has practiced in the area of
         commercial law for at least 10 years, selected in the manner
         established by the Commercial Arbitration Rules of the AAA.

         AGREEMENT CONTROLS: The Loan Documents shall include this Agreement and
         any prior loan agreement, letter agreement or other agreement between
         Bank and Borrowers or any one of them. In the event of a conflict
         between any of the provisions of this Agreement and any provisions of
         any other Loan Documents, the provisions of this Agreement shall
         control.

         ACCEPTANCE REQUIRED: It is a condition of this Agreement that Borrowers
         and Guarantors accept it in writing by signing the original, or a
         counterpart of the original which shall have the same effect as signing
         of a single original, and by returning the accepted Agreement with the
         Loan Fee to the Bank. If Borrowers and Guarantors fail to accept and
         return this Agreement with the Loan Fee, the Bank shall have no
         obligation under it.




NORWEST BANK ARIZONA,
NATIONAL ASSOCIATION



By: /s/ KEVIN KOSAN
    _______________________________
    Kevin Kosan, Vice President
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         Accepted and approved this 4th day of September, 1996.



Monterey Management Tucson, Inc.             Monterey Homes Tucson Corporation



By: /s/ Larry W. Seay                        By: /s/ Larry W. Seay
----------------------------------           ----------------------------------
Its: Vice President                          Its: Vice President


Monterey Management, Inc.                    Monterey Homes Corporation



By: /s/ Larry W. Seay                        By: /s/ Larry W. Seay
----------------------------------           ----------------------------------
Its: Vice President                          Its: Vice President


/s/ Bill Cleverly                             /s/ Steve Hilton
----------------------------------           ----------------------------------
Bill Cleverly, Guarantor                     Steve Hilton, Guarantor


/s/ Benee Hilton
----------------------------------
Benee Hilton, Guarantor
