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                                                                   EXHIBIT 10.13


                   [McGETTIGAN, WICK & CO., INC. LETTERHEAD]


                                 June 10, 1998


Mr. Evan M. Gruber
Chief Executive Officer
Modtech, Inc.
P.O. Box 1240
Perris, California 92570


Dear Evan:

     This letter is to confirm the retention by Modtech Inc. ("Modtech" or the 
"Company") of the firm of McGettigan, Wick & Co., Inc. ("McGettigan Wick") to 
provide financial advisory services to you, as the chief executive officer of 
Modtech, and to the Board of Directors of Modtech, when appropriate, relative 
to the structuring, evaluation, negotiation, documentation, and closing of
(i) the acquisition another company having a purchase price to Modtech of less
than $40 million, (ii) the acquisition of SPI Manufacturing, Inc., and/or (iii)
the sale or merger of Modtech (the contemplated "transactions"). Upon the
completion of the negotiations of the terms and conditions of any or all of the
transactions, we will oversee the documentation and closing process. In
addition, if the form of consideration is anything other than cash, we will
provide the Board of Directors with an opinion as to the actual value of the
proposed consideration, if such an evaluation is requested by Modtech's Board of
Directors.

     If the ultimate transaction is the sale of the Company, we will establish, 
from the purchase price for the Company, a pool that will be made available to 
senior management of Modtech. The amount of this pool will be determined by 
Mike Wick, you and me, and its allocation will be solely up to you. The purpose 
of the creation of this bonus pool is to properly involve the Company's senior 
management in this sale process and to provide an incentive to the senior 
management to remain in place during the period from the announcement of the 
sale of the Company until the closing of the sale. The actual amount of the 
pool will be approximately equal to the closing fee to be paid to McGettigan 
Wick.

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Mr. Evan M. Gruber
June 10, 1998
Page 2



       If required by the specific contemplated transaction, we will assist
Modtech in preparing an Executive Summary of the Company and its historical, 
current and prospective operations and financials. This Executive Summary will 
be structured for use as the lead-in to a package that will include the 1997 
10-K, Proxy Statement, recent press releases, and other pertinent publicly 
available data. This descriptive package will be shared with a limited number 
of potential acquirors identified by you and me. Based on our ownership in 
Modtech and our positions as directors of Modtech, McGettigan Wick will, as 
concerned principals and where mutually agreed with you, initiate the approach 
to these potential acquirors.

       Our fee for providing the aforementioned financial advisory services 
will be determined by the specific transaction:

              If the transaction is the acquisition of a company at a purchase
              price of less than $40 million, our free, payable upon closing,
              will be $600,000.

              If the transaction is an acquisition of SPI Manufacturing, our 
              fee, payable upon closing, will be $1,250,000.

              If the transaction is a sale of all of Modtech, our fee, payable
              upon closing, will be equal to $1,250,000, plus an incentive fee
              equal to (i) 3% of the increment in the sale proceeds if the price
              per share is greater than $20, but less than $22.50; (ii) 4% of
              the increment in the sale proceeds if the price per share is
              greater than $22.50 but less than $25; and (iii) 5% of the 
              increment in the sale proceeds if the price per share is greater
              than $25.

       There will be no up-front retainer fee.

       It is understood that Modtech will reimburse us within 15 days after 
receipt of documentation for any reasonable out-of-pocket expenses we might 
incur in connection with our services to the Company pursuant to this 
agreement. Such expenses are expected to include, but are not limited to, 
travel, telephone and courier expenses. The Company will also reimburse 
McGettigan Wick for reasonable professional fees, such as attorneys' and 
accountants' fees, as they become necessary and are authorized in advance by 
Modtech.
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     Mr. Evan M. Gruber
     June 10, 1998
     Page 3


          In connection with the services which McGettigan Wick has agreed to
     render to the Company hereunder, the Company shall indemnify McGettigan
     Wick and hold us harmless against any losses, claims, damages or
     liabilities to which McGettigan Wick may become subject in connection with
     our rendering of such services, and reimburse McGettigan Wick for any
     reasonable legal or other expenses reasonably incurred by us in connection
     with investigating, preparing to defend or defending any lawsuits, claims
     or other proceedings arising in any manner out of or in connection with the
     rendering of such services, unless such losses, claims, damages,
     liabilities or expenses arise out of the negligence or bad faith of
     McGettigan Wick. The Company agrees that the indemnification and
     reimbursement commitments set forth in this agreement shall apply whether
     or not McGettigan Wick is a formal party to any such lawsuits or other
     proceedings, that such commitments shall be in addition to any liability
     that the Company may have to McGettigan Wick at common law or otherwise,
     and that such commitments shall extend upon the terms set forth in this
     agreement to any controlling person, director, officer, owner, partner,
     employee or agent of McGettigan Wick and shall survive any termination of
     this agreement.

          McGettigan Wick shall indemnify Modtech and hold Modtech harmless
     against any losses, claims, damages or lawsuits (including reasonable
     attorney's fees) arising out of gross negligence or malfeasance of
     McGettigan Wick, its employees or its agents.

          In case any proceeding shall be instituted involving any person
     indemnified by this agreement, such person (the "indemnified party") shall
     promptly notify the Company and the Company, upon request of the
     indemnified party, shall retain counsel reasonably satisfactory to the
     indemnified party to represent the indemnified party and others the Company
     may designate in such proceeding and shall pay as incurred the fees and
     expenses of counsel relating to such proceeding. In any such proceeding,
     any indemnified party shall have the right to retain its own counsel at its
     own expense, except that the Company shall pay the reasonable fees and
     expenses of counsel retained by the indemnified party in the event that (i)
     the Company and the indemnified party shall have mutually agreed to the
     retention of such counselor, or (ii) the named parties to any such
     proceeding (including any impleaded parties) include both the Company and
     the indemnified party and representation of both parties by the same
     counsel would be inappropriate, in the reasonable opinion of the
     indemnified party, due to actual or potential differing interests between
     them. In no event shall     
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Mr. Evan M. Gruber
June 10, 1998
Page 4

the Company be liable for the fees and expenses of more than one counsel for all
indemnified parties in connection with any one action or separate but similar or
related actions in the same jurisdiction arising out of the same general
allegations or circumstances. The Company shall not be liable for any settlement
of any proceeding effected without its written consent, but if settled with such
consent or if there be a final judgment for the plaintiff, the Company agrees to
indemnify the indemnified party to the extent set forth in this agreement.

   
     This agreement may be terminated by Modtech or McGettigan Wick at any time 
with or without cause beginning six months after the date of the signing of this
agreement, effective upon receipt of written notice to that effect by the other 
party. Any such termination will not affect the compensation, reimbursement or 
indemnification provisions above, which will continue in full force and effect 
in accordance with their terms, with respect to obligations incurred or actions 
taken prior to termination of this agreement. We shall be entitled to full 
compensation in the event that, at any time prior to the expiration of one year 
after termination of this agreement. Modtech enters into any one of the 
contemplated transactions.
    

     Any advice, written or oral, rendered by McGettigan Wick pursuant to this 
letter may not be disclosed publicly without our prior written consent.

     This agreement shall be governed by the laws of the State of California 
without giving effect to that State's conflict of laws principles.

     Any offer for or sale of Modtech must be approved by Modtech's Board of 
Directors and/or Modtech's shareholders.
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  Mr. Evan M. Gruber
  June 10, 1998
  Page 5



        We look forward to assisting you in this effort. If the foregoing 
correctly sets forth the understanding between us, please so indicate by 
executing the enclosed copy of this letter and returning it to us.


                                        Very truly yours,


                                        McGETTIGAN, WICK & CO., INC.


                                        By:   /s/ Charles C. McGettigan
                                           ----------------------------
                                              Charles C. McGettigan



Agreed to and accepted this 11 day of June, 1998


MODTECH INC.


BY: /S/ Evan M. Gruber
   -------------------------------
   Evan M. Gruber
   Chief Executive Officer