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                                                                  Exhibit 10.3.2



                          SUBSIDIARY SECURITY AGREEMENT

         This Subsidiary Security Agreement (this "Agreement") is entered into
as of February 11, 2002, by MOBILE MINI I, INC., an Arizona corporation, MOBILE
MINI HOLDINGS, INC., a Delaware corporation, DELIVERY DESIGN SYSTEMS, INC., an
Arizona corporation, MOBILE MINI, LLC, a Delaware limited liability company,
MOBILE MINI, LLC, a California limited liability company, MOBILE MINI OF OHIO,
LLC, a Delaware limited liability company, and MOBILE MINI TEXAS LIMITED
PARTNERSHIP, LLP, a Texas limited liability partnership (each, together with
each additional Subsidiary of Mobile Mini, Inc. (the "Borrower") which becomes a
party hereto, a "Grantor" and collectively, the "Grantors"), in favor of the
financial institutions and their successors and assigns (the "Lenders") which
may now be or hereafter become parties to the Loan Agreement (as defined below),
and FLEET CAPITAL CORPORATION, for itself and as agent for the Lenders (the
"Agent"; and together with the Lenders, the "Secured Parties").

                                 R E C I T A L S

         WHEREAS, the Agent, the Lenders and Borrower, the parent of Grantors,
have entered into that certain Loan and Security Agreement, dated as of February
11, 2002 (as the same may be amended, supplemented, amended and restated or
otherwise modified from time to time, the "Loan Agreement"), providing for the
extension of credit by the Lenders to the Borrower. Capitalized terms used
herein and not otherwise defined herein shall have the meanings given to such
terms in the Loan Agreement; and;

         WHEREAS, as wholly-owned subsidiaries of Borrower, each Grantor is
materially interested in the financial success of Borrower; and

         WHEREAS, Borrower and Grantors are involved in an inter-related
business enterprise and will benefit from the financing provided by the Secured
Parties; and

         WHEREAS, the Lenders have required, as a condition to the extension of
credit under the Loan Agreement, that the Grantors execute and deliver this
Agreement.

         NOW, THEREFORE, in consideration of the premises and to induce the
Lenders to extend credit under the Loan Agreement, each Grantor agrees with the
Agent for its benefit and the ratable benefit of the Lenders as follows:

                                A G R E E M E N T

         1        Security Interests.

                  (a)      Security Interest in Collateral. To secure the prompt
payment and performance to Agent and each Lender of its Obligations under the
Guaranty and any other Loan
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Document (the "Secured Obligations"), each of the Grantors hereby grants to
Agent for the benefit of itself and each Lender a continuing Lien upon all such
Grantor's assets, including all of the following Property and interests in
Property of such Grantor, whether now owned or existing or hereafter created,
acquired or arising and wheresoever located:

                           (i)      Accounts;

                           (ii)     Certificated Securities;

                           (iii)    Chattel Paper, including Electronic Chattel
         Paper and Tangible Chattel Paper;

                           (iv)     Commercial Tort Claims;

                           (v)      Computer Hardware and Software and all
         rights with respect thereto, including, any and all licenses, options,
         warranties, service contracts, program services, test rights,
         maintenance rights, support rights, improvement rights, renewal rights
         and indemnifications, and any substitutions, replacements, additions or
         model conversions of any of the foregoing;

                           (vi)     Contract Rights;

                           (vii)    Deposit Accounts;

                           (viii)   Documents;

                           (ix)     Equipment;

                           (x)      Financial Assets;

                           (xi)     Fixtures;

                           (xii)    General Intangibles, including Payment
         Intangibles and Software;

                           (xiii)   Goods (including all of its Equipment,
         Fixtures and Inventory), and all accessions, additions, attachments,
         improvements, substitutions and replacements thereto and therefor;

                           (xiv)    Instruments;

                           (xv)     Intellectual Property;

                           (xvi)    Inventory;

                           (xvii)   Investment Property;

                           (xviii)  money (of every jurisdiction whatsoever);


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                           (xix)    Letter-of-Credit Rights;

                           (xx)     Payment Intangibles;

                           (xxi)    Security Entitlements;

                           (xxii)   Software;

                           (xxiii)  Supporting Obligations;

                           (xxiv)   Uncertificated Securities; and

                           (xxv)    to the extent not included in the foregoing,
         all other personal property of any kind or description;

together with all books, records, writings, data bases, information and other
property relating to, used or useful in connection with, or evidencing,
embodying, incorporating or referring to any of the foregoing, and all Proceeds,
products, offspring, rents, issues, profits and returns of and from any of the
foregoing; provided that to the extent that the provisions of any lease or
license of Computer Hardware and Software or Intellectual Property expressly
prohibit (which prohibition is enforceable under applicable law) any assignment
thereof, and the grant of security interest therein, Agent will not enforce its
security interest in such Grantor's rights under such lease or license (other
than in respect of the Proceeds thereof) for so long as such prohibition
continues, it being understood that upon request of Agent, such Grantor will in
good faith use reasonable efforts to obtain consent for the creation of a
security interest in favor of Agent (and to Agent's enforcement of such security
interest) in Agent's rights under such lease or license.

                  (b)      Other Collateral.

                           (i)      Commercial Tort Claims. Each Grantor shall,
         and shall cause its Subsidiaries to, promptly notify Agent in writing
         upon its obtaining knowledge of the incurrence of or obtaining a
         Commercial Tort Claim after the Closing Date against any third party
         and, upon request of Agent, promptly enter into an amendment to this
         Agreement and do such other acts or things deemed appropriate by Agent
         to give Agent a security interest in any such Commercial Tort Claim.

                           (ii)     Other Collateral. Each Grantor shall, and
         shall cause its Subsidiaries to, promptly notify Agent in writing upon
         acquiring or otherwise obtaining any material amount of Collateral
         after the date hereof consisting of Deposit Accounts, Investment
         Property, Letter of Credit Rights or Electronic Chattel Paper and, upon
         the request of Agent, promptly execute such other documents, and do
         such other acts or things deemed appropriate by Agent to deliver to
         Agent control with respect to such Collateral; promptly notify Agent in
         writing upon acquiring or otherwise obtaining any Collateral after the
         date hereof consisting of Documents or Instruments and, upon the
         request of Agent, will promptly execute such other documents, and do
         such other acts or things deemed appropriate by Agent to deliver to
         Agent possession of such Documents which are negotiable and Instruments
         (other than Instruments for which the aggregate


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         principal amount does not collectively exceed $100,000), and, with
         respect to nonnegotiable Documents, to have such nonnegotiable
         Documents issued in the name of Agent; and with respect to Collateral
         in the possession of a third party, other than Certificated Securities
         and Goods covered by a Document, obtain an acknowledgement from the
         third party that it is holding the Collateral for the benefit of Agent.

                  (c)      Lien Perfection; Further Assurances. Each Grantor
shall, and shall cause its Subsidiaries to, execute such UCC-1 financing
statements as are required by the UCC and such other instruments, assignments or
documents as are necessary to perfect Agent's Lien upon any of the Collateral
and shall take such other action as may be required to perfect or to continue
the perfection of Agent's Lien upon the Collateral. Unless prohibited by
applicable law, such Grantor hereby irrevocably authorizes Agent to execute (if
required) and file any such financing statements, including, without limitation,
financing statements that indicate the Collateral (i) as all assets of such
Grantor or its Subsidiaries, as applicable, or words of similar effect, or (ii)
as being of an equal or lesser scope, or with greater or lesser detail, than as
set forth in Subsection 1(a) above, on such Grantor's or the applicable
Subsidiary's behalf. Such Grantor, on behalf of itself and its Subsidiaries,
also hereby ratifies its authorization for Agent to have filed in any
jurisdiction any like financing statements or amendments thereto if filed prior
to the date hereof. The parties agree that a carbon, photographic or other
reproduction of this Agreement shall be sufficient as a financing statement and
may be filed in any appropriate office in lieu thereof. At Agent's request, such
Grantor shall, and shall cause its Subsidiaries to, also promptly execute or
cause to be executed and shall deliver to Agent any and all documents,
instruments and agreements deemed necessary by Agent to give effect to or carry
out the terms or intent of the Loan Documents. Such Grantor shall, and shall
cause its Subsidiaries to, mark all chattel paper to note Agent's Liens therein.

                  (d)      Lien on Realty. The due and punctual payment and
performance of the Obligations shall also be secured by the Lien created by
Mortgages upon all real Property of each Grantor and its Subsidiaries now or
hereafter owned. Each Mortgage shall be executed by such Grantor or the
applicable Subsidiary in favor of Agent. Each Mortgage shall be duly recorded,
at such Grantor's expense, in each office where such recording is required to
constitute a fully perfected first Lien on the real Property covered thereby.
Such Grantor shall deliver to Agent, at such Grantor's expense, mortgagee title
insurance policies issued by a title insurance company satisfactory to Agent,
which policies shall be in form and substance satisfactory to Agent and shall
insure a valid first Lien in favor of Agent, for the benefit of itself and the
Lenders, on the Property covered by each Mortgage, subject only to those
exceptions acceptable to Agent and its counsel. Such Grantor shall deliver to
Agent such other documents, including, without limitation, as-built survey
prints of the real Property, as Agent and its counsel may request relating to
the real Property subject to the Mortgages.

         2        Collateral Administration

                  (a)          General

                           (i)      Location of Collateral. All Collateral,
         other than Inventory in transit and motor vehicles, will at all times
         be kept by each Grantor at one or more of


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         business locations set forth in Exhibit 6.1.1 to the Loan Agreement, as
         updated pursuant to Section 6.3 of the Loan Agreement.

                           (ii)     Insurance of Collateral. Each Grantor shall
         maintain and pay for insurance upon all Collateral wherever located and
         with respect to the business of such Grantor, covering casualty,
         hazard, public liability, workers' compensation and such other risks in
         such amounts and with such insurance companies as are reasonably
         satisfactory to Agent. Such Grantor shall deliver certified copies of
         such policies to Agent as promptly as practicable, with satisfactory
         lender's loss payable endorsements, naming Agent as loss payee on any
         property insurance or business interruption insurance policies and as
         an additional insured on any liability insurance policies, and showing
         only such other loss payees, assignees and additional insureds as are
         satisfactory to Agent. Each policy of insurance or endorsement shall
         contain a clause requiring the insurer to give not less than 10 days'
         prior written notice to Agent in the event of cancellation of the
         policy for nonpayment of premium and not less than 30 days' prior
         written notice to Agent in the event of cancellation of the policy for
         any other reason whatsoever and a clause specifying that the interest
         of Agent shall not be impaired or invalidated by any act or neglect of
         such Grantor, any of its Subsidiaries or the owner of the Property or
         by the occupation of the premises for purposes more hazardous than are
         permitted by said policy. Such Grantor agrees to deliver to Agent,
         promptly as rendered, true copies of all reports made in any reporting
         forms to insurance companies.

         Unless such Grantor provides Agent with evidence of the insurance
         coverage required by this Agreement, Agent may purchase insurance at
         such Grantor's expense to protect Agent's interests in the Properties
         of such Grantor. This insurance may, but need not, protect the
         interests of such Grantor. The coverage that Agent purchases may not
         pay any claim that such Grantor makes or any claim that is made against
         such Grantor in connection with said Property. Such Grantor may later
         cancel any insurance purchased by Agent, but only after providing Agent
         with evidence that such Grantor has obtained insurance as required by
         this Agreement. If Agent purchases insurance, such Grantor will be
         responsible for the costs of that insurance, including interest and any
         other charges Agent may impose in connection with the placement of
         insurance, until the effective date of the cancellation or expiration
         of the insurance. The costs of the insurance may be added to the
         Obligations. The costs of the insurance may be more than the cost of
         insurance that such Grantor may be able to obtain on its own.

                           (iii)    Protection of Collateral. Neither Agent nor
         any Lender shall be liable or responsible in any way for the
         safekeeping of any of the Collateral or for any loss or damage thereto
         (except for reasonable care in the custody thereof while any Collateral
         is in Agent's or such Lender's actual possession) or for any diminution
         in the value thereof, or for any act or default of any warehouseman,
         carrier, forwarding agency, or other person whomsoever, but the same
         shall be at such Grantor's sole risk.

                  (b)          Administration of Accounts.

                           (i)      Records, Schedules and Assignments of
         Accounts. Each Grantor


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         shall, and shall cause each of its Subsidiaries and Affiliates to, keep
         accurate and complete records of its Accounts and all payments and
         collections thereon and shall submit to Agent on such periodic basis as
         Agent shall request a sales and collections report for the preceding
         period, in form consistent with the reports currently prepared by such
         Grantor with respect to such information. Concurrently with the
         delivery of each Borrowing Base Certificate by Borrower as required by
         Subsection 8.1.4 of the Loan Agreement, or more frequently as requested
         by Agent, from and after the date hereof, such Grantor shall deliver to
         Agent a detailed aging of all of Accounts of such Grantor, and upon
         Agent's request therefor, copies of proof of delivery and the original
         copy of all documents, including, without limitation, repayment
         histories and present status reports relating to the Accounts so
         scheduled and such other matters and information relating to the status
         of then existing Accounts as Agent shall reasonably request.

                           (ii)     Taxes. If an Account includes a charge for
         any tax payable to any governmental taxing authority, Agent is
         authorized, in its sole discretion, to pay the amount thereof to the
         proper taxing authority for the account of each Grantor or its
         Subsidiary and to charge such Grantor therefor, except for taxes that
         (i) are being actively contested in good faith and by appropriate
         proceedings and with respect to which such Grantor or such Subsidiary
         maintains reasonable reserves on its books therefor and (ii) would not
         reasonably be expected to result in any Lien other than a Permitted
         Lien. In no event shall Agent or any Lender be liable for any taxes to
         any governmental taxing authority that may be due by such Grantor or
         any of its Subsidiaries or Affiliates.

                           (iii)    Account Verification. Any of Agent's
         officers, employees or agents shall have the right, at any time or
         times hereafter, in the name of Agent, any designee of Agent or any
         Grantor, to verify the validity, amount or any other matter relating to
         any Accounts by mail, telephone, telegraph or otherwise; provided, that
         unless a Default or an Event of Default is then in existence, prior to
         conducting each set of verifications, Agent shall generally consult
         with such Grantor about the verification process. Such Grantor shall
         cooperate fully with Agent in an effort to facilitate and promptly
         conclude any such verification process.

                           (iv)     Maintenance of Dominion Account. Each
         Grantor shall maintain lockbox and blocked account arrangements
         acceptable to Agent with such banks as may be selected by such Grantor
         and be acceptable to Agent, for direct deposit of payments and other
         remittances. Such Grantor shall also maintain a Dominion Account or
         Accounts pursuant to lockbox and blocked account arrangements
         acceptable to Agent with such banks as may be selected by such Grantor
         and be acceptable to Agent. Such Grantor shall issue to any such banks
         an irrevocable letter of instruction directing such banks to deposit
         all payments or other remittances received in the lockbox and blocked
         accounts to the Dominion Account for application on account of the
         Obligations. All funds deposited in any Dominion Account shall
         immediately become the property of Agent, for the ratable benefit of
         Lenders, and such Grantor shall obtain the agreement by such banks in
         favor of Agent to waive any offset rights against the funds so
         deposited. In the event that the applicable bank is unwilling to waive
         such rights, such Grantor shall, upon Agent's request to do so,
         immediately transfer any funds deposited in such bank


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         accounts to a bank that will agree to waive such rights. Agent assumes
         no responsibility for such lockbox and blocked account arrangements,
         including, without limitation, any claim of accord and satisfaction or
         release with respect to deposits accepted by any bank thereunder.

                           (v)      Collection of Accounts, Proceeds of
         Collateral. To expedite collection, each Grantor shall endeavor in the
         first instance to make collection of its Accounts for Agent. All
         remittances received by such Grantor on account of Accounts, together
         with the proceeds of any other Collateral, shall be held as Agent's
         property, for its benefit and the benefit of Lenders, by such Grantor
         as trustee of an express trust for Agent's benefit and such Grantor
         shall immediately deposit same in kind in the lockboxes or a Dominion
         Account. Agent retains the right at all times after the occurrence and
         during the continuance of a Default or an Event of Default to notify
         Account Debtors that Accounts of such Grantor have been assigned to
         Agent and to collect such Accounts directly in its own name and to
         charge the collection costs and expenses, including attorneys' fees, to
         such Grantor.

                  (c)      Records and Reports of Inventory, Machinery and
Equipment. Each Grantor shall, and shall cause its Subsidiaries and Affiliates
to, keep records of its Inventory, and Equipment, which records shall be
complete and accurate in all material respects. Such Grantor shall furnish to
Agent updates of Inventory and Equipment reports as required by Section 6.3 of
the Loan Agreement concurrently with the delivery by Borrower of each Borrowing
Base Certificate described in Subsection 8.1.4 of the Loan Agreement or more
frequently as requested by Agent, which reports will be in such other format and
detail as Agent shall request and shall include a current list of all locations
of Inventory, Machinery and Equipment of such Grantor. Such Grantor shall
conduct an inventory no less frequently than annually of all Inventory on
premises owned or leased by such Grantor or any it is Subsidiaries and shall
provide to Agent a report based on each such physical inventory promptly
thereafter, together with such supporting information as Agent shall reasonably
request.

                  (d)      Administration of Equipment. Each Grantor shall, and
shall cause its Subsidiaries and Affiliates to, keep records of its Equipment
which shall be complete and accurate in all material respects itemizing and
describing the kind, type, quality, quantity and book value of its Equipment and
all dispositions made in accordance with this Agreement, and such Grantor shall
furnish Agent with a current schedule containing the foregoing information on at
least an annual basis and more often if reasonably requested by Agent. Promptly
after the reasonable request therefor by Agent, such Grantor shall deliver to
Agent any and all evidence of ownership, if any, of any Equipment.

                  (e)      Appraisals. When reasonably requested by Agent, each
Grantor shall provide the following: a report of Eligible Container Fleet
Inventory and Eligible Trailer Fleet Inventory by category and by item (in
detail), a report of Inventory, based upon a physical count, which shall
describe Inventory of such Grantor by category and by item (in detail) and
report the then appraised value (at lower of cost or orderly liquidation value)
of such Inventory, and a report of Equipment which shall describe such Grantor's
Equipment (in detail) and report the then appraised value (at lower of cost or
orderly liquidation value) of such Equipment. In addition,


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when requested by Agent after consultation with such Grantor regarding the scope
and cost of any such appraisal, such Grantor shall provide the Lenders, at such
Grantor's expense, with appraisals or updates thereof of any or all of the
Collateral from an Appraiser. Unless an Event of Default has occurred and is
continuing, the appraisals or updates thereof respecting container Inventory
held for lease shall not be requested more than twice during any twelve month
period, other than appraisals of such Inventory in connection with a Permitted
Acquisition. Such Grantor acknowledges and agrees that Agent intends to have
performed such appraisal or update with respect to container Inventory held for
lease at least twice during each twelve month period during the term of this
Agreement.

         3                 REPRESENTATIONS  AND  WARRANTIES

                  (a)      General Representations and Warranties .To induce
Agent and each Lender to enter into this Agreement and to make advances
hereunder, each Grantor warrants, represents and covenants to Agent and each
Lender that:

                           (i)      Power and Authority. Each Grantor is duly
         authorized and empowered to enter into, execute, deliver and perform
         this Agreement. The execution, delivery and performance of this
         Agreement has been duly authorized by all necessary corporate or other
         relevant action and do not and will not (i) require any consent or
         approval of any of the shareholders, partners or members, as the case
         may be, of any Grantor; (ii) contravene any Grantors' charter, articles
         or certificate of incorporation, partnership agreement, certificate of
         formation, by-laws, limited liability company agreement, operating
         agreement or other organizational documents (as the case may be); (iii)
         violate, or cause any Grantor 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 any Grantor;
         (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 any Grantor is a party or by which it or its Properties may be
         bound or affected; or (v) result in, or require, the creation or
         imposition of any Lien (other than Permitted Liens) upon or with
         respect to any of the Properties now owned or hereafter acquired by
         Grantor.

                           (ii)     Title to Properties; Priority of Liens. Such
         Grantor has good, indefeasible and marketable title to and fee simple
         ownership of, or valid and subsisting leasehold interests in, all of
         its real Property, and good title to all of the Collateral and all of
         its other Property, in each case, free and clear of all Liens except
         Permitted Liens. such Grantor has paid or discharged all lawful claims
         which, if unpaid, might become a Lien against any of such Grantor's
         Properties that is not a Permitted Lien. The Liens granted to Agent
         under Section 5 hereof and under the Security Documents are first
         priority Liens, subject only to Permitted Liens.

                           (iii)    Accounts. Agent may rely, in determining
         which Accounts are Eligible Accounts, on all statements and
         representations made by such Grantor with respect to any Account or
         Accounts of such Grantor. With respect to each of such Accounts,
         whether or not such Account is an Eligible Account, unless otherwise


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         disclosed to Agent in writing: (A) it is genuine and in all respects
         what it purports to be, and it is not evidenced by a judgment; (B) it
         arises out of a completed, bona fide sale and delivery of goods or
         rendition of services by such Grantor, in the ordinary course of its
         business and in accordance with the terms and conditions of all
         purchase orders, contracts or other documents relating thereto and
         forming a part of the contract between such Grantor and the Account
         Debtor and the Account Debtor is not an Affiliate of such Grantor; (C)
         it is for a liquidated amount maturing as stated in the duplicate
         invoice covering such sale or rendition of services; (D) there are no
         facts, events or occurrences which in any way impair the validity or
         enforceability of any Accounts or tend to reduce the amount payable
         thereunder from the face amount of the invoice and statements delivered
         or made available to Agent with respect thereto; (E) to such Grantor's
         knowledge, the Account Debtor thereunder (1) had the capacity to
         contract at the time any contract or other document giving rise to the
         Account was executed and (2) such Account Debtor is Solvent; and (F) to
         Grantor's knowledge, there are no proceedings or actions which are
         threatened or pending against the Account Debtor thereunder which might
         result in any material adverse change in such Account Debtor's
         financial condition or the collectibility of such Account (other than
         non-material disputes involving de minimis amounts arising in the
         ordinary course of business).

                           (iv)     Equipment. The Equipment of each Grantor is
         in good operating condition and repair.

                  (b)      Continuous Nature of Representations and Warranties.
Each representation and warranty contained in this Agreement and the other Loan
Documents shall be continuous in nature and shall remain accurate, complete in
all material respects and not misleading at all times during the term of this
Agreement, except for changes in the nature of such Grantor's or one of such
Grantor's Subsidiary's or Affiliate's business or operations that would render
the information in any exhibit attached hereto or to any other Loan Document
either inaccurate, incomplete or misleading, so long as Majority Lenders have
consented to such changes or such changes are expressly permitted by this
Agreement.

                  (c)      Survival of Representations and Warranties. All
representations and warranties of each Grantor contained in this Agreement or
any of the other Loan Documents shall survive the execution, delivery and
acceptance thereof by Agent and each Lender and the parties thereto and the
closing of the transactions described therein or related thereto.

         4        Covenants.

                  (a)      Landlord, Processor and Storage Agreements. Each
Grantor shall provide Agent on request with copies of all agreements between
such Grantor and any landlord, processor, distributor, warehouseman or consignee
which owns any premises at which any Collateral may, from time to time, be kept

                  (b)      Deposit and Brokerage Accounts. For each deposit
account or brokerage account that any Grantor at any time opens or maintains,
such Grantor shall, at Agent's request


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and option, pursuant to an agreement in form and substance satisfactory to
Agent, cause the depository bank or securities intermediary, as applicable, to
agree to comply at any time with instructions from Agent to such depository bank
or securities intermediary, as applicable, directing the disposition of funds
from time to time credited to such deposit or brokerage account, without further
consent of such Grantor.

                  (c)      Maintenance of Equipment. Each Grantor shall make or
cause to be made all necessary replacements of and repairs to Equipment so that
the operating efficiency thereof shall be maintained and preserved, reasonable
wear and tear excepted, except where the failure to so maintain the same would
not reasonably be expected to have a Material Adverse Effect. Such Grantor will
not permit any Equipment to become affixed to any real Property leased to such
Grantor so that an interest arises therein under the real estate laws of the
applicable jurisdiction unless the landlord of such real Property has executed a
landlord waiver or leasehold mortgage in favor of and in form reasonably
acceptable to Agent, and such Grantor will not permit any of the Equipment of
such Grantor to become an accession to any personal Property other than
Equipment that is subject to first priority (except for Permitted Liens) Liens
in favor of Agent.

         5        Right to Enter. Each Grantor shall permit representatives of
Agent, and during the continuation of any Default or Event of Default any
Lender, from time to time, as often as may be reasonably requested, but only
during normal business hours, to visit and inspect the Properties of such
Grantor and each of its Subsidiaries, inspect, audit and make extracts from its
books and records, observe the use of any part of the Collateral, or otherwise
determine whether such Grantor is in compliance with the terms of this
Agreement. Agent, if no Default or Event of Default then exists, shall give such
Grantor reasonable prior notice of any such inspection or audit.

         6        Further Assurances. Each Grantor shall execute and file any
financing or continuation statement, or amendments thereto, and such other
instruments or notices as may be necessary or desirable, which Agent may
reasonably request in order to perfect and preserve the perfection and the
priority of the security interests granted or purported to be granted under this
Agreement. Such Grantor agrees that, at Agent's option, this Agreement, or a
photocopy hereof, may be filed by Agent as a financing statement, and that such
Grantor's execution hereof shall constitute the execution by such Grantor of a
financing statement.

         7        Defaults. Each Grantor shall be in default under this
Agreement upon the happening of any Event of Default under (and as defined in)
the Loan Agreement.

         Upon the occurrence and during the continuance of an Event of Default,
Agent shall have and may exercise from time to time the following rights and
remedies:

                           (i)      All of the rights and remedies of a secured
         party under the UCC or under other applicable law, and all other legal
         and equitable rights to which Agent or Lenders may be entitled, all of
         which rights and remedies shall be cumulative and shall be in addition
         to any other rights or remedies contained in this Agreement or any of
         the other Loan Documents, and none of which shall be exclusive.


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                           (ii)     The right to take immediate possession of
         the Collateral, and to (i) require each Grantor and its Subsidiaries to
         assemble the Collateral, at such Grantor's expense, and make it
         available to Agent at a place designated by Agent which is reasonably
         convenient to both parties, and (ii) enter any premises where any of
         the Collateral shall be located and to keep and store the Collateral on
         said premises until sold (and if said premises be the Property of such
         Grantor or any Subsidiary of such Grantor, such Grantor agrees not to
         charge, or permit any of its Subsidiaries to charge, Agent for storage
         thereof).

                           (iii)    The right to sell or otherwise dispose of
         all or any Collateral in its then condition, or after any further
         manufacturing or processing thereof, at public or private sale or
         sales, with such notice as may be required by law, in lots or in bulk,
         for cash or on credit, all as Agent, in its sole discretion, may deem
         advisable. Agent may, at Agent's option, disclaim any and all
         warranties regarding the Collateral in connection with any such sale.
         Each Grantor agrees that five (5) Business Days' written notice to such
         Grantor or any of its Subsidiaries of any public or private sale or
         other disposition of Collateral shall be reasonable notice thereof, and
         such sale shall be at such locations as Agent may designate in said
         notice. Agent shall have the right to conduct such sales on such
         Grantor's or any of its Subsidiaries' premises, without charge
         therefor, and such sales may be adjourned from time to time in
         accordance with applicable law. Agent shall have the right to sell,
         lease or otherwise dispose of the Collateral, or any part thereof, for
         cash, credit or any combination thereof, and Agent, on behalf of
         Lenders, may purchase all or any part of the Collateral at public or,
         if permitted by law, private sale and, in lieu of actual payment of
         such purchase price, may set off the amount of such price against the
         Obligations. The proceeds realized from the sale of any Collateral may
         be applied, after allowing two (2) Business Days for collection, first
         to the costs, expenses and attorneys' fees incurred by Agent in
         collecting the Obligations, in enforcing the rights of Agent and
         Lenders under the Loan Documents and in collecting, retaking,
         completing, protecting, removing, storing, advertising for sale,
         selling and delivering any Collateral, second to the interest due upon
         any of the Obligations; and third, to the principal of the Obligations.
         If any deficiency shall arise, each Grantor shall remain jointly and
         severally liable to Agent and Lenders therefor.

                           (iv)     Agent is hereby granted a license or other
         right to use, without charge and consistent with the applicable
         Grantor's reasonable quality control requirements, each Grantor's and
         each of such Grantor's Subsidiary's labels, patents, copyrights,
         licenses, rights of use of any name, trade secrets, tradenames,
         trademarks and advertising matter, or any Property of a similar nature,
         as it pertains to the Collateral, in completing, advertising for sale
         and selling any Collateral and such Grantor's and each of its
         Subsidiary's rights under all licenses and all franchise agreements
         shall inure to Agent's benefit.

         8        Costs and Expenses. Each Grantor agrees to pay on demand all
costs and expenses, including legal fees, incurred or paid by Agent in
preparing, executing or amending this Agreement, and in exercising its rights
and remedies or protecting its interests hereunder.


                                       11
<PAGE>
         9        Right of Set Off. In addition to any rights now or hereafter
granted under applicable law and not by way of limitation of any such rights,
during the continuance of any Event of Default, each Lender is hereby authorized
by each Grantor at any time or from time to time, with prior written consent of
Agent and with reasonably prompt subsequent notice to such Grantor (any prior or
contemporaneous notice to such Grantor being hereby expressly waived) to set off
and to appropriate and to apply any and all (i) balances held by such Lender at
any of its offices for the account of such Grantor or any of its Subsidiaries
(regardless of whether such balances are then due to such Grantor or its
Subsidiaries), and (ii) other property at any time held or owing by such Lender
to or for the credit or for the account of such Grantor or any of its
Subsidiaries, against and on account of any of the Obligations of Borrower;
provided, that each Lender exercising such rights shall notify Agent thereof
prior to exercise, shall refrain from exercising such right until Agent shall
have confirmed to such Lender that such exercise will not prejudice the rights
of the Lenders, and any amount received as a result of the exercise of such
rights shall be shared in accordance with Subsection 3.8 of the Loan Agreement.
Any Lender exercising a right to set off shall, to the extent the amount of any
such set off exceeds its Revolving Loan Percentage of the amount set off,
purchase for cash (and the other Lenders shall sell) interests in each such
other Lender's pro rata share of the Obligations as would be necessary to cause
such Lender to share such excess with each other Lender in accordance with their
respective Revolving Loan Percentages. Each Grantor agrees, to the fullest
extent permitted by law, that any Lender may exercise its right to set off with
respect to amounts in excess of its pro rata share of the Obligations and upon
doing so shall deliver such excess to Agent for the benefit of all Lenders in
accordance with the Revolving Loan Percentages..

         10       Notices. All notices, approvals, consents or other
communications to Agent required or desired to be given hereunder shall be in
the form and manner, and delivered to Agent at its addresses, as set forth in
Section 12.8 of the Loan Agreement. All notices, approvals, consents or other
communications to Grantors required or desired to be given hereunder shall be in
the form and manner, and delivered to Borrower at its addresses, as set forth in
Section 12.8 of the Loan Agreement.

         11       Termination of Security Agreement. This Security Agreement and
the security interest hereunder shall terminate upon the full and final payment
in cash and performance of all the Obligations by Borrower under the Loan
Agreement and termination of the Revolving Loan Commitments. Notwithstanding
anything to the contrary herein, this Security Agreement (including all
representations, warranties and covenants contained herein) shall continue to be
effective or be reinstated, as the case may be, if at any time any amount
received by any Lender in respect of the Secured Obligations is rescinded or
must otherwise be restored or returned by Lender upon or in connection with the
insolvency, bankruptcy, dissolution, liquidation or reorganization of any
Grantor or otherwise, all as though such payment had not been made.

         12       Headings. The headings in this Agreement are for purposes of
reference only and shall not otherwise affect the meaning or construction of any
provision of this Agreement.

         13       Amendments. Any amendment or waiver of any provision of this
Agreement and any consent to any departure by any Grantor from any provision of
this Agreement shall be effective only if made or given in compliance with all
of the terms and provisions of Section


                                       12
<PAGE>
11.10 of the Loan Agreement.

         14       Entire Agreement. This Agreement and the Loan Documents are
intended by the parties as a final expression of their agreement and is intended
as a complete and exclusive statement of the terms and conditions thereof.
Acceptance of or acquiescence in a course of performance rendered under this
Agreement shall not be relevant to determine the meaning of this Agreement even
though the accepting or acquiescing party had knowledge of the nature of the
performance and opportunity for objection.

         15       Severability. The provisions of this Agreement are severable,
and if any clause or provision shall be held invalid or unenforceable in whole
or in part in any jurisdiction, then such invalidity or unenforceability shall
affect in that jurisdiction only such clause or provision, or part thereof, and
shall not in any manner affect such clause or provision in any other
jurisdiction or any other clause or provision of this Agreement in any
jurisdiction.

         16       Successors and Assigns. All rights of Agent hereunder shall
inure to the benefit of its successor and assigns. No Grantor shall assign any
of its interest under this Agreement without the prior written consent of Agent.
Any purported assignment inconsistent with this provision shall, at the option
of Agent, be null and void.

         17       Governing Law. THE VALIDITY, INTERPRETATION AND ENFORCEMENT OF
THIS AGREEMENT AND ANY DISPUTE ARISING OUT OF OR IN CONNECTION WITH THIS
AGREEMENT, WHETHER SOUNDING IN CONTRACT, TORT, EQUITY OR OTHERWISE, SHALL BE
GOVERNED BY THE INTERNAL LAWS (AS OPPOSED TO THE CONFLICTS OF LAWS PROVISIONS)
AND DECISIONS OF THE STATE OF CALIFORNIA.

         18       Submission to Jurisdiction. ALL DISPUTES AMONG THE ANY OF THE
GRANTORS AND THE LENDERS (OR THE AGENT ACTING ON THEIR BEHALF) ARISING UNDER
THIS AGREEMENT, WHETHER SOUNDING IN CONTRACT, TORT, EQUITY OR OTHERWISE, SHALL
BE RESOLVED ONLY BY STATE AND FEDERAL COURTS LOCATED IN LOS ANGELES, CALIFORNIA,
AND THE COURTS TO WHICH AN APPEAL THEREFROM MAY BE TAKEN; PROVIDED, HOWEVER,
THAT THE AGENT, ON BEHALF OF THE LENDERS, SHALL HAVE THE RIGHT, TO THE EXTENT
PERMITTED BY APPLICABLE LAW, TO PROCEED AGAINST ANY OF THE GRANTORS OR THEIR
PROPERTY IN ANY LOCATION REASONABLY SELECTED BY THE AGENT IN GOOD FAITH TO
ENABLE THE AGENT TO REALIZE ON SUCH PROPERTY, OR TO ENFORCE A JUDGMENT OR OTHER
COURT ORDER IN FAVOR OF THE AGENT. EACH OF THE GRANTORS WAIVES ANY OBJECTION
THAT IT MAY HAVE TO THE LOCATION OF THE COURT IN WHICH THE AGENT HAS COMMENCED A
PROCEEDING ARISING UNDER THIS AGREEMENT, INCLUDING, WITHOUT LIMITATION, ANY
OBJECTION TO THE LAYING OF VENUE OR BASED ON FORUM NON CONVENIENS.

         19       Service of Process. EACH OF THE GRANTORS HEREBY IRREVOCABLY
DESIGNATES CT CORPORATIONS SYSTEMS AS THE DESIGNEE, APPOINTEE AND


                                       13
<PAGE>
AGENT OF THE GRANTORS TO RECEIVE, FOR AND ON BEHALF OF THE GRANTORS, SERVICE OF
PROCESS IN SUCH RESPECTIVE JURISDICTIONS IN ANY LEGAL ACTION OR PROCEEDING WITH
RESPECT TO THIS LOAN AGREEMENT OR ANY OTHER LOAN DOCUMENT. IT IS UNDERSTOOD THAT
A COPY OF SUCH PROCESS SERVED ON SUCH AGENT AT ITS ADDRESS WILL BE PROMPTLY
FORWARDED BY MAIL TO SUCH GRANTOR, BUT FAILURE OF ANY OF THE GRANTORS TO RECEIVE
SUCH COPY SHALL NOT AFFECT IN ANY WAY THE SERVICE OF SUCH PROCESS.

         20       Jury Trial. EACH OF THE GRANTORS, THE AGENT AND THE LENDERS
EACH HEREBY WAIVE ANY RIGHT TO A TRIAL BY JURY. INSTEAD, ANY DISPUTES WILL BE
RESOLVED IN A BENCH TRIAL.

         21       Limitation of Liability. NEITHER THE AGENT NOR ANY LENDER
SHALL HAVE ANY LIABILITY TO THE ANY OF THE GRANTORS (WHETHER SOUNDING IN TORT,
CONTRACT, OR OTHERWISE) FOR LOSSES SUFFERED BY ANY OF THE GRANTORS IN CONNECTION
WITH, ARISING OUT OF, OR IN ANY WAY RELATED TO THE TRANSACTIONS OR RELATIONSHIPS
CONTEMPLATED BY THIS AGREEMENT, OR ANY ACT, OMISSION OR EVENT OCCURRING IN
CONNECTION THEREWITH, UNLESS IT IS DETERMINED BY A FINAL AND NONAPPEALABLE
JUDGMENT OR COURT ORDER BINDING ON THE AGENT OR ANY SUCH LENDER, THAT THE LOSSES
WERE THE RESULT OF ACTS OR OMISSIONS CONSTITUTING GROSS NEGLIGENCE OR WILLFUL
MISCONDUCT.

         22       Delay; Waiver. No delay in enforcing or failing to enforce any
right under this Agreement by Lender shall constitute a waiver by Lender of such
right. No waiver by Lender of any default hereunder shall be effective unless in
writing, nor shall any waiver operate as a waiver of any other default or of the
same default on a future occasion.

         23       Counterparts. This Agreement may be executed in any number of
counterparts, 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.

         24       Additional Grantors. From time to time subsequent to the date
hereof, additional Subsidiaries of Borrower may become parties hereto as
additional Grantors (the "Additional Grantors"), by executing a counterpart (the
"Counterpart") substantially in the form of Exhibit A hereto. Upon delivery of
any such Counterpart to the Agent, notice of which is hereby waived by Grantors,
each such Additional Grantor shall be a Grantor and shall be as fully a party
hereto as if such Additional Grantor were an original signatory hereto. Each
Grantor expressly agrees that its obligations arising hereunder shall not be
affected or diminished by the addition or release of any other Grantor
hereunder, nor by any election of Agent not to cause any Subsidiary of Borrower
to become an Additional Grantor hereunder. This Agreement shall be fully
effective as to any Grantor that is or becomes a party hereto regardless of
whether any other Person becomes or fails to become or ceases to be a Grantor
hereunder.

         25       Interpretation of Agreement. Time is of the essence in each
provision of this Agreement of which time is an element. All terms not defined
herein or in the Loan Agreement


                                       14
<PAGE>
shall have the meaning set forth in the applicable Uniform Commercial Code,
except where the context otherwise requires. To the extent a term or provision
of this Agreement conflicts with the Loan Agreement, the Loan Agreement shall
control with respect to the subject matter of such term or provision. Acceptance
of or acquiescence in a course of performance rendered under this Agreement
shall not be relevant in determining the meaning of this Agreement even though
the accepting or acquiescing party had knowledge of the nature of the
performance and opportunity for objection

                     [remainder of page intentionally blank]


















                                       15
<PAGE>
         IN WITNESS WHEREOF, each of the Grantors has executed and delivered
this Subsidiary Security Agreement as of the date set forth in the first
paragraph hereof.

                                GRANTORS:

                                MOBILE MINI I, INC.,
                                an Arizona corporation
                                      /s/ Lawrence Trachtenberg
                                      Title: Executive Vice President

                                MOBILE MINI HOLDINGS, INC.,
                                a Delaware corporation

                                      /s/ Lawrence Trachtenberg
                                      Title: President

                                DELIVERY DESIGN SYSTEMS, INC.,
                                an Arizona corporation

                                      /s/ Lawrence Trachtenberg
                                      Title: Executive Vice President

                                MOBILE MINI, LLC,
                                a Delaware limited liability company

                                      /s/ Lawrence Trachtenberg
                                      Title: Executive Vice President and CFO

                                MOBILE MINI, LLC,
                                a California limited liability company

                                      /s/ Lawrence Trachtenberg
                                      Title: Executive Vice President and CFO

                                MOBILE MINI OF OHIO, LLC,
                                a Delaware limited liability company

                                      /s/ Lawrence Trachtenberg
                                      Title: Executive Vice President and CFO


<PAGE>
                                    MOBILE MINI TEXAS LIMITED
                                    PARTNERSHIP, LLP,
                                    a Texas limited liability partnership

                                      /s/ Lawrence Trachtenberg
                                      Title: Treasurer
<PAGE>
                                                                    EXHIBIT A TO
                                                   SUBSIDIARY SECURITY AGREEMENT

                              [FORM OF COUNTERPART]

                                   COUNTERPART

         COUNTERPART (this "Counterpart"), dated _______, is delivered pursuant
to Section 24 of the Subsidiary Security Agreement referred to below. The
undersigned hereby agrees that this Counterpart may be attached to the
Subsidiary Security Agreement, dated as of February 11, 2002 (as it may be from
time to time amended, modified or supplemented, the "Subsidiary Security
Agreement"; capitalized terms used herein not otherwise defined herein shall
have the meanings ascribed therein), by Mobile Mini I, Inc., an Arizona
corporation, Mobile Mini Holdings, Inc., a Delaware corporation, Delivery Design
Systems, Inc., an Arizona corporation, Mobile Mini, LLC, a Delaware limited
liability company, Mobile Mini, LLC, a California limited liability company,
Mobile Mini of Ohio, LLC, a Delaware limited liability company, and Mobile Mini
Texas Limited Partnership, LLP, a Texas limited liability partnership, in favor
of Fleet Capital Corporation, for itself and as agent (the "Agent"). The
undersigned by executing and delivering this Counterpart hereby becomes a
Grantor under the Subsidiary Security Agreement in accordance with Section 24
thereof and agrees to be bound by all of the terms thereof.



                                    [NAME OF ADDITIONAL GRANTOR]



                                    By: ________________________________________

                                         Name: _________________________________
                                         Title: ________________________________