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                                                                  EXHIBIT 10.3.5

                               FIRST AMENDMENT TO
                AMENDED AND RESTATED LOAN AND SECURITY AGREEMENT

            This FIRST AMENDMENT TO AMENDED AND RESTATED LOAN AND SECURITY
AGREEMENT (this "First Amendment") is dated as of January 14, 2004, and entered
into by and among FLEET CAPITAL CORPORATION ("Fleet"), a Rhode Island
corporation with an office at 15260 Ventura Boulevard, Suite 400, Sherman Oaks,
California 91403, individually as a Lender and as Agent ("Agent") for itself and
any other financial institution which is or becomes a party to the Loan
Agreement referred to below (each, a "Lender" and collectively, the "Lenders"),
the LENDERS signatory hereto and MOBILE MINI, INC., a Delaware corporation with
its chief executive office and principal place of business at 7420 South Kyrene
Road, Suite 101, Tempe, Arizona 85283.

            Whereas, Borrower, Agent, Deutsche Bank Securities Inc. and
Washington Mutual Bank, as Co-Documentation Agents, Bank One, NA and JP Morgan
Chase Bank, as Co-Syndication Agents, and the Lenders have entered into that
certain Amended and Restated Loan and Security Agreement dated as of February
11, 2002, as amended and restated as of June 26, 2003 (as it may be further
amended, restated, amended and restated, supplemented or otherwise modified from
time to time, the "Loan Agreement"); capitalized terms used in this First
Amendment without definition shall have the meanings given such terms in the
Loan Agreement; and

            Whereas, Borrower has requested an amendment to the Loan Agreement
to permit it to repurchase certain Securities; and

            Whereas, the Lenders are willing to agree to amend the Loan
Agreement, subject to the conditions and on the terms set forth herein;

            NOW THEREFORE, in consideration of the premises and the mutual
agreements set forth herein, Borrower, the Lenders and Agent agree as follows:

            1. AMENDMENT TO LOAN AGREEMENT. Subject to the conditions and on the
terms set forth in this First Amendment and in reliance on the representations
and warranties of Borrower set forth in this First Amendment, the Loan Agreement
is hereby amended as follows:

                  1.1 ADDITION OF NEW SUBSECTION 7.1.26. A new Subsection 7.1.26
is added to the Loan Agreement to read as follows:

                        7.1.26 Margin Regulations. Neither Borrower nor any
      Subsidiary is generally engaged in the business of purchasing or selling
      "margin stock" (as defined in Regulation U of the Board of Governors of
      the Federal Reserve System), or extending credit for the purpose of
      purchasing or carrying "margin stock". Less than 15% of the assets of
      Borrower constitute "margin stock." To the extent that Borrower uses Loan


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      proceeds to acquire shares of its own Securities, Borrower intends to
      cause such acquired shares to be cancelled or maintained as treasury stock
      by Borrower.

                  1.2 AMENDMENT TO SUBSECTION 8.2.6. Subsection 8.2.6 of the
Loan Agreement is hereby amended to delete the word "and" before clause (v) in
the proviso, to change the period at the end of clause (v) to a comma, and to
add the following thereafter: "and, Borrower may purchase on the open market
Securities consisting of its common stock for an aggregate amount not to exceed
$10,000,000 if, (A) both before and after giving effect to such purchase, no
Default or Event of Default exists or would result therefrom and Borrower has
Availability of at least $30,000,000, (B) such purchase is in compliance with
the Senior Note Documents and (C) all shares of such Securities so purchased are
thereafter immediately cancelled or shall have the status of treasury stock of
Borrower. For purposes of this Subsection 8.2.6, the determination of whether a
Event of Default exists under Section 8.3 after giving effect to such Restricted
Payment shall be based on pro forma calculations of the financial covenants as
of the end of the most recent fiscal quarter for which financial statements have
been delivered to the Lenders, giving effect to any Loan and Restricted Payment
made hereunder after the last day of such most recent fiscal quarter. Each
request for a Loan to make a Restricted Payment under this Subsection 8.2.6
shall be made under a separate request for borrowing and shall be accompanied by
calculations in reasonable detail showing compliance with this Subsection 8.2.6.

            2. REPRESENTATIONS AND WARRANTIES OF THE BORROWER. In order to
induce the Lenders and Agent to enter into this First Amendment, Borrower
represents and warrants to each Lender and Agent that the following statements
are true, correct and complete:

                  2.1 CORPORATE ACTION. Borrower is duly authorized and
empowered to enter into, execute, deliver and perform this First Amendment and
the Loan Agreement as amended hereby and Guarantors are duly authorized to enter
into, execute, deliver and perform the Consent of Guarantors and Reaffirmation
Agreement attached hereto (the "Guarantor Consent"). The execution, delivery and
performance of this First Amendment, the Loan Agreement as amended hereby and
the Guarantor Consent, and the purchase of the Securities in accordance with the
terms hereof, have been duly authorized by all necessary corporate or other
relevant action and do not and will not (i) require any consent or approval of
the shareholders of Borrower or any of the Guarantors; (ii) contravene
Borrower's or any of the Guarantors' charter or articles or certificate of
incorporation or other organizational documents, as applicable; (iii) violate,
or cause Borrower or any Guarantor to be in default under, any provision of any
law, rule, regulation, order, writ, judgment, injunction, decree, determination
or award in effect having applicability to Borrower or any Guarantor; (iv)
result in a breach of or constitute a default under any indenture or loan or
credit agreement or any other agreement, lease or instrument to which Borrower
or any Guarantor is a party or by which it or its Properties may be bound or
affected (including without limitation the Senior Note Documents); or (v) result
in, or require, the creation or imposition of any Lien upon or with respect to
any of the Properties now owned or hereafter acquired by Borrower or any
Guarantor. As of the date hereof, the Collateral does not include any "margin
stock" (as defined in Regulation U of the Board of Governors of the Federal
Reserve Board.


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                  2.2 LEGALLY ENFORCEABLE AGREEMENT. This First Amendment and
the Guarantor Consent have been duly executed and delivered by Borrower and the
Guarantors. Each of this First Amendment and the Loan Agreement as amended
hereby is a legal, valid and binding obligation of Borrower, enforceable against
it in accordance with its terms, and the Guarantor Consent is a legal, valid and
binding obligation of the Guarantors, enforceable against each of them in
accordance with its terms, except in each case as limited by applicable
bankruptcy or insolvency laws, and by general principles of equity.

                  2.3 SOLVENT FINANCIAL CONDITION. Borrower is Solvent.

                  2.4 NO DEFAULT OR EVENT OF DEFAULT. No event has occurred and
is continuing or will result from the execution and delivery of this First
Amendment that would constitute a Default or an Event of Default. Borrower is in
compliance with the terms of the Senior Note Documents.

                  2.5 NO MATERIAL ADVERSE EFFECT. No event has occurred that has
resulted, or could reasonably be expected to result, in a Material Adverse
Effect.

                  2.6 REPRESENTATIONS AND WARRANTIES. Each of the
representations and warranties contained in the Loan Documents is and will be
true and correct in all material respects on and as of the date hereof and as of
the effective date of this First Amendment, except to the extent that such
representations and warranties specifically relate to an earlier date, in which
case they were true, correct and complete in all material respects as of such
earlier date.

            3. CONDITIONS TO EFFECTIVENESS OF THIS FIRST AMENDMENT. This First
Amendment shall be effective only if and when signed by, and when counterparts
hereof shall have been delivered to the Agent or its counsel (by hand delivery,
mail or telecopy) by, Borrower and the Majority Lenders and only if and when
each of the following conditions is satisfied:

                  3.1 CONSENT OF GUARANTORS. Each of the Guarantors shall have
executed and delivered to Agent the Guarantor Consent.

                  3.2 NO DEFAULT OR EVENT OF DEFAULT; ACCURACY OF
REPRESENTATIONS AND WARRANTIES. No Default or Event of Default shall exist and
each of the representations and warranties made by the various parties herein
and in or pursuant to the Loan Documents shall be true and correct in all
material respects as if made on and as of the date on which this First Amendment
becomes effective (except that any such representation or warranty that is
expressly stated as being made only as of a specified earlier date shall be true
and correct as of such earlier date), and Borrower shall have delivered to Agent
a certificate confirming such matters.

                  3.3 OTHER DOCUMENTS. Agent shall have received such documents
as Agent may reasonably request in connection with this First Amendment.

            4. EFFECTIVE DATE. This First Amendment shall become effective on
the date ( the "First Amendment Effective Date") of the satisfaction of the
conditions set forth in Section 3.


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            5. EFFECT OF THIS FIRST AMENDMENT. From and after the First
Amendment Effective Date, all references in the Loan Documents to the Loan
Agreement shall mean the Loan Agreement as amended hereby. Except as expressly
amended hereby or waived herein, the Loan Agreement and the other Loan
Documents, including the Liens granted thereunder, shall remain in full force
and effect, and are hereby ratified and confirmed.

            6. GOVERNING LAW. THIS FIRST AMENDMENT HAS BEEN NEGOTIATED AND
DELIVERED IN AND SHALL BE DEEMED TO HAVE BEEN MADE IN LOS ANGELES, CALIFORNIA.
THIS FIRST AMENDMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE
LAWS OF THE STATE OF CALIFORNIA.

            7. COMPLETE AGREEMENT. This First Amendment sets forth the complete
agreement of the parties in respect of any amendment to any of the provisions of
any Loan Document or any waiver thereof.

            8. CATCHLINES & COUNTERPARTS. The catchlines and captions herein are
intended solely for convenience of reference and shall not be used to interpret
or construe the provisions hereof. This First Amendment may be executed by one
or more of the parties to this First Amendment on any number of separate
counterparts (including by telecopy), each of which when so executed and
delivered shall be deemed an original, but all of which shall together
constitute one and the same agreement.

         [signatures follow; remainder of page intentionally left blank]


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            IN WITNESS WHEREOF, this First Amendment To Amended and Restated
Loan and Security Agreement has been duly executed on the day and year specified
at the beginning of this First Amendment To Amended and Restated Loan and
Security Agreement.

                                      MOBILE MINI, INC., a Delaware corporation



                                      By:
                                         ---------------------------------------
                                      Name:  Lawrence Trachtenberg
                                      Title: Executive Vice President



                                      FLEET CAPITAL CORPORATION,
                                      a Rhode Island corporation,
                                      as Agent and as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Matthew R. Van Steenhuyse
                                      Title: Senior Vice President



                                      JP MORGAN CHASE BANK, as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Donna DiForio
                                      Title: Vice President


                                      BANK ONE, NA, with its main office in
                                      Chicago, Illinois, as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Steve Reinhart
                                      Title: First Vice President
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                                      WASHINGTON MUTUAL BANK, as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Terri K. Lins
                                      Title: Vice President



                                      GE COMMERCIAL DISTRIBUTION FINANCE
                                      f/k/a Deutsche Financial Services Corp.,
                                      as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Joseph Kinkenon
                                      Title: Vice President



                                      U.S. BANK NATIONAL ASSOCIATION,
                                      as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Joseph P. Howard
                                      Title: Vice President



                                      PNC BANK, NATIONAL ASSOCIATION,
                                      as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Lawrence Weinstein
                                      Title: Vice President



                                      THE PROVIDENT BANK, as a Lender
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                                      By:
                                         ---------------------------------------
                                      Name:  Marshall M. Stuart
                                      Title: Vice President



                                      BANK LEUMI USA, as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Jacques Delvoye
                                      Title: Vice President



                                      DEUTSCHE BANK TRUST COMPANY AMERICAS, as
                                      a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Mark E. Funk
                                      Title: Director



                                      CIBC, INC., as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  George Knight
                                      Title: Managing Director



                                      NATIONAL CITY BANK, as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Chris Kytzidis
                                      Title: Vice President
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                                      LASALLE BUSINESS CREDIT, LLC, as a Lender



                                      By:
                                         ---------------------------------------
                                      Name:  Thomas J. Brennan
                                      Title: Vice President