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                                                                    EXHIBIT 10.6

December 26, 2003

Government Properties Trust, Inc.
Mr. Thomas D. Peschio, President/CEO
10250 Regency Circle, Suite #100
Omaha, NE 68114-3754

RE:   Revolving Acquisition Line of Credit

Dear Mr. Peschio:

Based upon the financial information furnished, First National Bank of Omaha
("Lender") hereby commits to make the following described loan under the terms
and conditions hereinafter set forth:

BORROWER:           Government Properties Trust, Inc., or its assigns in which
                    it has controlling interest

GUARANTOR:          Government Properties Trust, Inc.

LENDER:             First National Bank of Omaha

FACILITY TYPE:      Revolving Line of Credit, to be used for real estate
                    acquisition purposes.

LOAN AMOUNT:        $50,000,000.00

LOAN ADVANCES:      A.) ACQUISITION ADVANCES shall not exceed 70% of
                    the lesser of the purchase price or appraised value of the
                    acquired property.

                    B.) DEPOSIT ADVANCES (for purchase deposits or permanent
                    mortgage good faith deposits) shall be secured by deposits
                    held by First National Capital Markets, Inc. Up to a maximum
                    of $25,000,000 may be utilized for Letters of Credit.

COLLATERAL:         A.) ACQUISITION ADVANCES: First Mortgages or Deeds of Trust,
                    Security Agreements, and Assignment of Rents and Leases on
                    acquired real estate.
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                       Government Properties Trust, Inc.

                    B.) DEPOSIT ADVANCES: Control Agreement between Borrower,
                    Guarantor, Lender and First National Capital Markets, Inc.

INTEREST RATE:      Prime Rate, Floating (as published by the Wall Street
                    Journal) with a floor of 4.00%.

TERM:               364 days

REPAYMENT:          Monthly payment of interest only based on the amount
                    advanced. Acquisition advances will be repaid upon closing
                    of the permanent financing. Deposit advances will be repaid
                    at the time of acquisition closing or permanent loan
                    closing. Acquisition advances will be limited to a maximum
                    of 6 months. In the event the line is not renewed prior to
                    the 6 months and the line is not replaced by another bank
                    group, then a new loan for that specific property will be
                    negotiated for a term of not more than 12 months.

PREPAYMENT:         The Line of Credit shall be open to prepayment at any time
                    without penalty or fee.

ORIGINATION FEE:    $ 250,000 (0.50% of the Commitment Amount) which is
                    payable on or before closing.

ADVANCE FEE:        0.50% of each advance. Additional fees will be
                    applicable to Letters of Credit.

FINANCIAL
 COVENANTS:         All advances that would increase the balance
                    outstanding under this facility will be subject to the
                    following:

                    1.   Minimum Tangible Net Worth not less than $ 90 million

                    2.   Total Liabilities to Tangible Net Worth shall be 4.0 or
                         less

                    3.   Minimum Debt Service Coverage Ratio of 1.2 times.

NEGATIVE COVENANTS: Limitations on other investments, i.e. Properties
                    under development, undeveloped land, unconsolidated
                    affiliates, etc.

AFFIRMATIVE
 COVENANTS:         Maintenance of corporate existence and REIT
                    status, maintenance of insurance; payment of taxes and other
                    liabilities; delivery of financial statements; distributions
                    not to exceed 100% of FFO for most recent 4 quarters, unless


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                       Government Properties Trust, Inc.

                    required to maintain REIT status. Other covenants as
                    appropriate.

ELIGIBLE
 PROPERTIES:        All properties submitted for inclusion must be
                    federal government leased properties and improvements
                    acceptable to Lender and must have an executed lease
                    agreement acceptable to Lender, including a minimum of 10
                    years remaining on the lease term.

USE OF FUNDS: Loan funds will be used to provide acquisition financing
(short-term) for the purchase of the federal government leased properties
(predominantly office buildings) that have a minimum of 10 years left on the
lease before a lease expiration or a lease termination date. Loan funds may also
be used to provide deposits for purchase contracts or good faith deposits with
potential permanent mortgage lenders.

LOAN DOCUMENTS: A.) ACQUISITION ADVANCES shall be secured by:

      a)    $50,000,000.00 Revolving Loan Agreement

      b)    Promissory Notes on the individual properties;

      c)    First Mortgages or Deeds of Trust on individual properties

      d)    Assignment of Rents and Leases;

      e)    Security Agreement covering all other tangible and intangible assets
            owned in connection with the individual properties;

      f)    Uniform Commercial Code Financing Statements;

      g)    Environmental Indemnity Agreement;

      h)    Master Guaranty Agreement executed by Guarantor;

      i)    Assignment of major construction contract(s) (if applicable);

      j)    Assignment of Architectural contract(s) (if applicable);

      k)    Notice of Commencement (if applicable); and

      l)    Such additional documents, as Lender shall require.

                B.) DEPOSIT ADVANCES shall be secured by:

      a)    Control Agreement between Borrower, Guarantor, Lender and First
            National Capital Markets, Inc.;

      b)    $50,000,000.00 Revolving Loan Agreement; and

      c)    Such additional documents, as Lender shall require.


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                       Government Properties Trust, Inc.

      The form and content of all above mentioned loan documents shall be
reasonably satisfactory to Lender's counsel.

REQUIREMENTS PRIOR TO LOAN CLOSING: At least seven (7) days prior to the closing
date, Borrower shall have furnished to Lender each of the following in form and
content acceptable to Lender:

a)    TITLE: Evidence that title to the Collateral shall be good and marketable,
      free and clear of all defects, liens, encumbrances, security interests,
      restrictions and easements which Lender has not otherwise approved. Such
      evidence shall specifically include:

i.      Copies of all documents affecting title to the Collateral;

ii.     Evidence that ingress and egress from the project is by public streets;
        and

iii.    Evidence that all utilities serving the project are located in the
        public right-of-way abutting the project and if connected to the project
        by passing over property which is not public right-of-way, are connected
        to the project by means of easements which have been granted, are
        acceptable to Lender, and which will be insured through proper title
        insurance.

b)    TITLE INSURANCE: A commitment to issue, on the closing date, an ALTA
      mortgagee's policy of title insurance to Lender, American Land Title
      Association Loan Policy 10-17-92 or such other form as Lender shall
      approve, for the full amount of the loan. The title insurance policy, when
      issued, shall contain a comprehensive zoning endorsement and any and all
      other endorsements which lender require. Title shall be subject to those
      exceptions, as Lender shall approve.

c)    SURVEY: An ALTA As-Built Survey of the real estate comprising the property
      being acquired, identifying all easements and utility locations prepared
      by a land surveyor duly registered and in good standing in the State
      (where the property is located) to be in accordance with the survey
      standards as listed in the Exhibit "A" attached, shall be provided.

d)    APPRAISAL: The Lender will require an MAI Appraisal Report on each
      individual property funded under the Line of Credit. The appraisal is to
      be ordered by the Lender at Borrower's cost. The appraisal report must be
      in compliance with all of the minimum standards as required by FIRREA in
      their uniform appraisal standards adopted June 7, 1994, dealing with
      federally regulated institutions. Loan not to exceed 70% of appraised
      value.

e)    "PHASE I" SITE ASSESSMENT REPORT: The Lender will require a satisfactory
      Phase I Environmental Assessment Report covering each individual property
      funded under the Line of Credit. The report, ordered by the Lender at
      Borrower's cost, will include, as a minimum, a 40 year title search of all
      past users and owners of the property being mortgaged.


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                       Government Properties Trust, Inc.

f)    INSURANCE: Fire and extended coverage insurance for the full insurable
      value of the building, including comprehensive general liability
      insurance. All insurance policies required hereunder shall be issued by
      companies, on forms, in amounts and with deductibles acceptable to Lender,
      and shall show Lender as "additional insured" and "loss payee" with a
      standard non-contributory mortgagee clause in favor of Lender. Such policy
      shall provide that there shall be no cancellation or modification without
      less than thirty (30) days prior written notice to Lender. All such
      policies shall be renewed during the term of the loan and copies of same
      shall be provided to Lender at least thirty (30) days prior to the
      termination date of any then current policy. Rent loss coverage of at
      least twelve (12) months shall be required.

g)    TAXES AND ASSESSMENTS: Evidence that all installments of general real
      estate taxes, special taxes or assessments and the like are paid on all
      properties acquired under the subject Line of Credit.

h)    LEGAL COMPLIANCE: Evidence from local governmental authorities having
      jurisdiction that the acquisition property complies with all zoning
      requirements, fire marshal requirements, city code requirements, and any
      other local ordinance relative to the property's development.

i)    FINANCIAL STATEMENTS: Audited financial statements of the Borrower and
      Guarantor shall be provided to Lender upon request. Lender may reasonably
      require rent rolls and operating and financial statements on the acquired
      property.

j)    U.C.C./TAX LIEN/JUDGMENT SEARCHES: U.C.C., tax lien and judgment searches
      against Borrower, Guarantor, and such other parties as Lender may require,
      showing that the personal property owned by the Borrower and/or Guarantor,
      as applicable, is free from all security interests, liens, encumbrances,
      and judgments, except the prior security interest to Lender.

k)    LEGAL CAPACITY: Lender will be given evidence that the persons executing
      the loan documents on behalf of the Borrower and Guarantor have legal
      capacity and authority to enter into this mortgage transaction and to
      execute the loan documents.

SPECIAL MORTGAGE PROVISIONS: The loan documents shall provide, in addition to
 all other provisions required by lender:

a.)   FINANCIAL STATEMENTS AND REPORTS: Guarantor and Borrower shall furnish to
      Lender, within ninety (90) days after the close of each fiscal year, and
      thereafter upon request, current operating and financial statements and/or
      tax returns of Borrower and Guarantors, in form satisfactory to Lender, as
      Lender shall request.

b.)   DUE ON SALE OR ENCUMBRANCE: It shall be an event of default if Borrower
      shall, without the prior written consent of Lender, sell, convey,
      alienate, mortgage or encumber the Collateral, or any part thereof, or any
      interest therein, or shall be divested of its title thereto, whether by
      operation of law or otherwise.


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                       Government Properties Trust, Inc.


CONDITIONS OF CLOSING: The Lender's obligation to disburse the loan contemplated
 hereunder, or any portion thereof, shall be conditioned upon the following
 occurring:

a)    DELIVERY OF LOAN DOCUMENTS; COMPLIANCE: Borrower shall have delivered to
      Lender all documents and other items required hereunder, which shall be in
      such form and content, as Lender shall prescribe. Borrower shall have
      satisfied each provision and condition of this commitment in a manner
      reasonably acceptable to Lender, or Lender shall have waived, in writing,
      Borrower's compliance with a specific provision. Borrower shall provide a
      certified copy of the limited liability company or partnership agreement
      and tax identification number of the Borrower.

b)    PAYMENT OF COSTS BY BORROWER: Regardless of whether the loan closes,
      Borrower shall pay all of the Lender's costs in connection with the
      preparation, closing and disbursement of the loan, including but not
      limited to, title insurance premiums, survey costs, recording fees and
      taxes, fees and expenses of Lender's counsel and all other out-of-pocket
      costs and expenses incurred by Lender in connection with this loan.

c)    NO ADVERSE CHANGE: Borrower shall warrant that there has been no
      deterioration in the financial condition of Borrower or Guarantor and that
      the financial information heretofore submitted to Lender by Borrower and
      Guarantor is accurate and complete in all material respects. Lender will
      be promptly notified of any event which has, or with the passage of time
      could, cause an adverse change in the financial condition of the Borrower
      or Guarantor, so long as any indebtedness represented by loan documents
      remain unpaid.

AFFILIATE AND LOAN PARTICIPANTS: Lender reserves the right to participate this
loan out to various "affiliate and participant" banks. Accordingly, these banks
would receive and approve of relevant financial data. Borrower hereby authorizes
Lender's submission of relevant financial data to its affiliate and participant
banks.

CREDIT AGREEMENT: A credit agreement must be in writing to be enforceable under
Nebraska law. To protect you and us from any misunderstandings or
disappointments, any contract, promise, undertaking, or offer to forebear
repayment of money or to make any other financial accommodation in connection
with this loan of money or grant or extension of credit, or any amendment of,
cancellation of, waiver of, or substitution for any or all of the terms or
provisions of any instrument or document executed in connection with this loan
of money or grant or extension of credit, must be in writing to be effective.

BORROWER ACCEPTANCE OF COMMITMENT: Borrower's acceptance of the commitment must
be by Borrower's approval of this commitment by executing and returning a
duplicate copy of the commitment letter not later than December 30, 2003 at 4:00
p.m.

CANCELLATION OF COMMITMENT: If Borrower has not satisfied all of the
requirements prior to closing date, time being of the essence, or if Borrower
has breached or defaulted in the observance or performance of any of the
undertakings, warranties or representations of

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                       Government Properties Trust, Inc.

Borrower in connection with this loan, the Lender shall have the option without
giving prior notice to borrower to cancel the commitment and terminate all of
the Lender's obligations hereunder (including, without limitation, the
obligation to make any disbursements of the mortgage loan proceeds) and,
thereupon, Lender shall have the right to pursue any other and further legal and
equitable remedies available to Lender.

COMMITMENT EXPIRATION: Closing of this loan transaction must occur within 60
days from the date of commitment acceptance or this commitment shall be
considered null and void.

                              FIRST NATIONAL BANK OF OMAHA

                              By: /s/ Daniel M. Shultz
                                  ------------------------------------------
                                    Daniel M. Shultz, Vice President

                                   ACCEPTANCE

The above outlined terms and conditions are hereby accepted this 29 day of
December, 2003.

Federal ID #_________________       GOVERNMENT PROPERTIES TRUST, INC.,
                                    a___________________ corporation


                                    By:  /s/ Nancy D. Olson - CFO
                                         ----------------------------

                                    Its:  Chief Financial Officer
                                         ----------------------------

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                       Government Properties Trust, Inc.

                                   EXHIBIT "A"

                               SURVEY REQUIREMENTS

A.    A plat of the subject property showing the following:

      (i) The boundary line and area of the subject property showing all
dimensions and all appurtenant easements by courses and distances showing the
area of the subject property, and each parcel thereof, in square feet. If the
subject property is composed of all or portions of several lots or other legal
subdivisions, the boundaries of each should be indicated by dotted lines and the
proper lot number or legal subdivision designation shown. If the survey
comprises more than one parcel, it should show interior lines and facts
sufficient to insure contiguity. Points of beginning used in the description of
the subject property should be identified.

      (ii) The location and type of any buildings, improvements, or structures
on the subject property, the dimensions and area thereof and the distances
therefrom to the nearest facing exterior property lines of the subject property.

      (iii) The location of all easements and rights-of-way affecting or
benefiting the subject property (each of which must be identified by referenced
by the volume and page where recorded).

      (iv) The location of all building set back lines on the subject property.

      (v) All encroachments, conflicts or protrusions onto adjacent property,
streets or alleys of any improvements on the subject property and all
encroachments, conflicts or protrusions onto the subject property from adjacent
property.

      (vi) All abutting dedicated public streets providing access to the subject
property, showing the width and the name thereof, and all sidewalks, parkways,
curbs and driveways, including the street address of all building improvements,
should be shown.

      (vii) All fences (both perimeter and cross) and all walls and other
improvements along the property lines with dimensions. All party walls of
buildings or other structures on the property line indicating the thickness of
the portions thereon on each side of the property and the nature of the use of
said walls on each side.

      (viii) The location of any railroad tracks and boundaries of railway
rights-of-way affecting the subject property.

      (ix) All surface wires and cables crossing, entering or leaving the
subject property, indicating the amount of cross arm or wire overhang and all
anchors and/or guy wires affecting the subject property except ordinary wire
service drops.

      (x) The character and location of all telephone, telegraph or electric
lines; water, sewer, oil or gas pipelines, etc., on or across the surveyed
property and on adjoining properties if they appear to affect the enjoyment of
the surveyed property; the points of connection of all service lines with the
public system.

      (xi) A directional indicator showing North.


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                       Government Properties Trust, Inc.

      B. Any portion of the subject property which is located in a flood plain
or in any other flood hazard or flood danger area as designated by applicable
governmental authorities; if none, so state.

      C. A legal description (metes and bounds) of the subject property which
must coincide with the boundaries shown on the plat and which must be identical
with the description of the subject property, as described in the title
insurance commitment.

      D. (As-built survey only) Show buildings, improvements, and parking area
(including the number of spaces provided by such parking areas and the number of
spaces required by applicable zoning ordinances for such improvements based on
the intended use of the improvements), as well as all matters set forth in A.
through C. above.

      E. The certification signed and sealed by the surveyor, which must be in
substantially the following form:

      TO:   (Title Insurance Company)

            (Borrower)

            (Lender)

            I hereby certify that on the _______ day of ________________, 19___:

      (a) This survey was made on the ground as per the field notes shown on
this survey and correctly shows:

            (i) the boundaries and areas of the subject property and the size,
            location and type of buildings and improvements thereon and the
            distance therefrom to the nearest facing exterior property lines of
            the subject property;

            (ii) the location of all rights-of-way, easements, and any other
            chartable matters of record shown on Commitment for Title Insurance
            No. __________________, dated _____________________, issued by
            ___________________, as agent for ___________________________ (Title
            Insurance Company) (or of which I have knowledge or have been
            advised, whether or not of record) affecting or benefiting the
            subject property,

            (iii) the location of the parking areas on the subject property
            showing the number of parking spaces provided thereby,

            (iv) all abutting dedicated public streets providing access to the
            subject property, together with the width and name thereof, and

            (v) all other significant items on the subject property;

      (b) Except as set forth below, there are no:

            (i) encroachments upon the subject property by improvements on
            adjacent property,


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                       Government Properties Trust, Inc.


            (ii) encroachments on adjacent property, streets or alleys by any
            improvements on the subject property,

            (iii) party walls,

            (iv) conflicts or protrusions.

The exceptions to the above statements are as follows (if none, so state):

      (c) Adequate ingress to and egress from the subject property is provided
by (name of streets), and the same being paved, dedicated public right(s)-of-way
maintained by (name of maintaining authority).

      (d) All required building setback lines on the subject property are
located as shown hereon.

            -----------------------------
            (Signature of Surveyor)

            Registered Land Surveyor
            Registration No.
                            -------------

            -----------------------------
            Name

            -----------------------------
            Address

            -----------------------------
            City, State, and Zip Code

            -----------------------------
            Telephone Number

            -----------------------------
            Job Number of Surveyor


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                       Government Properties Trust, Inc.

                                   EXHIBIT "B"

                                CONTROL AGREEMENT
               REGARDING SECURITY INTEREST IN INVESTMENT PROPERTY

      This Agreement, made as of the __th day of _________, 20__, by and between
First National Bank of Omaha ("BANK"), a national banking association
established at Omaha, Nebraska, ______________________(CUSTOMER"), a resident of
____________________, and First National Capital Markets, Inc. ("COMPANY"), a
corporation with offices at 1620 Dodge St., Omaha, Nebraska

                                    RECITALS:

      A. CUSTOMER is indebted to BANK as the result of one or more promissory
notes, or other evidence of indebtedness. Such indebtedness, whether resulting
from a promissory note, guaranty, letter of credit, or any other document or
cause, is herein called an "OBLIGATION".

      B. For purposes of this agreement, all capitalized terms not otherwise
defined herein have the same meanings as defined in Nebraska Uniform Commercial
Code Section 8-102 (a);

      C. COMPANY is either the issuer of, or a SECURITIES INTERMEDIARY as to,
the FINANCIAL ASSET described as pledged securities in CUSTOMER's Agency Account
#________ (which, together with all cash and stock dividends, stock splits,
rights to subscribe, and any property exchanged for the foregoing, and proceeds
of the same, are hereafter called the "COLLATERAL"); and

      D. CUSTOMER has provided BANK a security interest in the COLLATERAL, and
CUSTOMER desires to provide BANK with control over the COLLATERAL, as such term
is defined in Nebraska Uniform Commercial Code Section 8-106.

      Now, therefore, the parties hereto agree as follows:

      1. COMPANY agrees that it will comply with INSTRUCTIONS and ENTITLEMENT
ORDERS originated by BANK as to the COLLATERAL, without further consent of
CUSTOMER. Until otherwise instructed, CUSTOMER is to receive any cash dividends
attributable to the COLLATERAL.

      2. Notwithstanding the provisions of paragraph 1, above, CUSTOMER retains
the right to originate instructions to COMPANY as to substitutions for the
COLLATERAL, until BANK provides written notice to COMPANY of a default by
CUSTOMER as to the OBLIGATION, following receipt of which only BANK may
originate instructions to COMPANY as to the COLLATERAL.

      3. This Agreement is executed in Nebraska and is subject to the laws of
Nebraska, including the Nebraska Uniform Commercial Code. This Agreement is
effective until terminated by a written notice executed by BANK delivered to
COMPANY, or until the COLLATERAL is no longer registered to or owned by
CUSTOMER.

      4. This Agreement is effective until terminated by a written notice
executed by BANK delivered to COMPANY, or until the COLLATERAL is no longer
registered to or owned by CUSTOMER. Nonetheless, this agreement shall be renewed
on an annual basis, if necessary, subject to approval and acceptance by COMPANY.


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                       Government Properties Trust, Inc.

In witness whereof, the parties have executed this agreement as of the date
first set forth above.

First National Bank of Omaha "BANK"


By
   ---------------------      --------------------
Its:
   -----------------------------------------------



First National Capital Markets, Inc. "COMPANY"

By
   ---------------------      --------------------
Its:
   -----------------------------------------------



-----------------------------------------
 "CUSTOMER"

------------------------------------------
 "CUSTOMER"


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