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                           WINDSOR FINANCIAL GROUP, INC.

                          INVESTMENT MANAGEMENT AGREEMENT



     This Agreement made this first day of December, 1997 by and between
Mercantile National Bank, ("CLIENT") and Windsor Financial Group, Inc., 
("WFG"). 

     WHEREAS, CLIENT wishes to retain WFG as its investment adviser to invest
and reinvest certain assets upon the terms and conditions set forth below; and

     WHEREAS, WFG is willing to provide such investment advisory services to
CLIENT pursuant to these terms and conditions.  

     NOW, THEREFORE, the parties agree as follows:

1.   INVESTMENT MANAGEMENT SERVICES.  WFG will provide CLIENT with the
     investment management services outlined in Schedule A attached hereto.  As
     CLIENT's investment advisor, WFG will keep CLIENT's investment portfolio
     under continuous supervision.  WFG will have no discretionary authority
     with respect to specific investment decisions; rather, WFG will make
     investment recommendations to an officer(s) designated by CLIENT for
     approval prior to execution.  
     
2.   SAFEKEEPING OF ASSETS.  All assets for which WFG acts as investment adviser
     shall at all times be held by a custodian bank or broker/dealer in a
     segregated safekeeping account.  CLIENT shall furnish WFG with a copy of
     all custody agreements between CLIENT and any designated custodian.  WFG
     will not be responsible for the safekeeping of CLIENT's securities held by
     a custodian. 
     
3.   EXECUTION OF INVESTMENT DECISIONS.  In order to execute CLIENT's investment
     decisions, WFG will:
     
     a.   purchase, sell, invest and reinvest the assets of the portfolio
          according to CLIENT's instructions; and
          
     b.   develop and maintain with CLIENT such procedures as are needed to
          effect proper delivery of securities purchased and sold; to facilitate
          payments, collections and the transmittal of funds; and to ensure the
          prompt investment of any available cash, including income, the
          proceeds of sales or redemptions, and such additional capital as may
          be allocated from time to time to CLIENT's account.  
          
4.   COMPENSATION FOR SERVICES. The investment management fee for services
     provided by WFG is set forth in Schedule B attached hereto.  All fee
     statements will be sent out at the beginning of each calendar quarter and
     are due upon receipt. 
     
5.   REPORTS/MEETINGS.  WFG will submit a quarterly status report to CLIENT
     listing the assets of the portfolio and the portfolio's value as of the end
     of the quarter.  WFG will meet the CLIENT at least once per year, and more
     frequently at CLIENT's request, to discuss the performance of CLIENT's
     investment portfolio and any other matters relating to this Agreement.  
     
6.   SELECTION OF BROKERS.  The board of directors will have sole discretion to
     select brokers from a list provided by WFG to perform brokerage services in
     connection with the purchase and sale of assets in the portfolio.  
     
7.   PAYMENT OF EXPENSES.  WFG shall be responsible for the payment of all costs
     and expenses related to the management of CLIENT's account, except for the
     following expenses which shall be CLIENT's obligation:  

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     a.   Fees paid for account or legal services rendered to the portfolio at
          CLIENT's request;
          
     a.   Brokerage commissions and charges, including transfer taxes and
          similar taxes incurred in the purchase and sale of securities for
          CLIENT's account; and
     
     c.   Interest and taxes imposed upon CLIENT's portfolio with respect to its
          income or ownership of securities.
     
8.   SERVICES TO THIRD PARTIES.  WFT is free to render services to third parties
     similar to those rendered to CLIENT under this Agreement, except that no
     services rendered to third parties may inhibit or interfere with WFG's
     performance of services hereunder. 
     
9.   EFFECTIVE DATE/TERMINATION.  The effective date of this Agreement shall be
     January 1, 1998 and it shall continue into effect until December 31, 1998,
     whereupon it may be terminated by either party with 30 days of prior
     written notice.  Client will be entitled to a refund of any unearned
     advisory fees as of the date of termination.  
     
10.  NOTICES.  Any written notice required under this Agreement shall be
     personally delivered or forwarded by first class mail, postage prepaid,
     addressed to WFG as follows:
     
     
                          Windsor Financial Group, Inc.
                       222 South Ninth Street, Suite 2790
                             Minneapolis, MN 55402
                  Attention:  James A. Powell, Managing Director
     
     
     and addressed to CLIENT as follows:
     
     
                             Mr. Joseph W. Kiley III
                          Executive Vice President & CFO
                            Mercantile National Bank
                             1840 Century Park East
                              Los Angeles, CA 90067
     
     
     or at such other address or place as shall be directed in writing by the
     parties.  
     
11.  GOVERNING LAW.  This Agreement shall be construed and enforced in
     accordance with the laws of the State of Minnesota.  
     
12.  LIABILITY OF WFG.  WFG, its officers, employees and agents, shall not be
     liable for any losses sutained by CLIENT's investment portfolio as a result
     of the decrease in value of any securities in the portfolio or for any
     other reason, whether or not such losses are attributable to any opinion,
     action or failure to act by WFG, unless WFG fails to act in good faith or
     is guilty of gross negligence or willful misconduct.  Nothing herein shall
     in any way constitute a waiver or limitation of CLIENT's rights under state
     and federal securities laws.  
     
13.  ASSIGNMENT.  This Agreement is not assignable by either party without the
     written consent of the other party.  
     
14.  INVESTMENT ADVISERS ACT.  WFG is, and will continue to be during the term
     of this Agreement, registered under and in compliance with the Investment
     Advisers Act of 1940.  

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IN WITNESS WHEREOF, the parties executed this Agreement as of the day and year
first written above.  


WINDSOR FINANCIAL GROUP, INC.           CLIENT

By  /s/  JAMES A. POWELL                By  /s/  JOSEPH W. KILEY III
   --------------------------------        -------------------------------------
         James A. Powell                         Joseph W. Kiley III 
         Managing Director                       Executive Vice President & CFO


Receipt is hereby acknowledged of a copy of Form ADV, Part II, as required by
the Securities Exchange Commission under Rule 204-3, under the Investment
Adviser's Act of 1940.  



By  /s/  JOSEPH W. KILEY III 
   --------------------------------
         Joseph W. Kiley III

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ATTACHMENT A


BANK INVESTMENT MANAGEMENT
SERVICES PROVIDED

I.    Fee based professional portfolio management to assist in the development 
      of appropriate investment asset strategies by qualified investment
      professionals.
      
II.   Enhanced reporting capabilities including quarterly performance evaluation
      against an established benchmark.
      
III.  Development of investment portfolio policies and strategies within the
      context of bank management goals.
      
IV.   Credit review of asset purchases.
      
V.    Regular contact with professional portfolio manager regarding the
      development of specific bank strategies.
      
VI.   Client meetings as appropriate or deemed necessary by management with a
      minimum of an annual on site meeting.
      
VII.  Execution on all trades as necessary to implement bank investment
      strategies.
      
VIII. Quantitative analysis of all purchases.

IX.   Assistance in the pricing of public and other large deposits.

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                                   SCHEDULE B
                                        
                                        
                                        
                                        
                        INVESTMENT PORTFOLIO MANAGEMENT
                         WINDSOR FINANCIAL GROUP, INC.
                                        
                                        
                                        
                    FEE SCHEDULE FOR 1/1/98 THROUGH 12/31/98
                                        
                                        
                                        
                                        
                                        
     Par Value of the Portfolio as of 12/31/97 times .0007 (7 basis points)
                                        
                                        
                                        
To be paid in four installments at the beginning of each calendar quarter.