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                                                                   EXHIBIT 3.1a

                         CERTIFICATE OF AMENDMENT OF THE
                AMENDED AND RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                                MOBILE MINI, INC.


         MOBILE MINI, INC., a corporation organized and existing under the
General Corporation Law of the State of Delaware (the "Corporation"), does
hereby certify:

         FIRST: That at a meeting of the Board of Directors of the Corporation
resolutions were duly adopted setting forth proposed amendments to the amended
and restated certificate of incorporation of the corporation, declaring said
amendments to be advisable and calling a meeting of the Stockholders of the
Corporation for consideration thereof. The resolutions setting forth the
proposed amendments are as follows:

                  RESOLVED, that Article IV of the Amended and Restated
         Certificate of Incorporation is amended in its entirety to read as
         follows:

                           "FOURTH: The total number of shares of all classes of
                  stock which the Corporation shall have authority to issue is
                  one hundred million (100,000,000) of which ninety-five million
                  (95,000,000) shares shall be common stock with the par value
                  of one cent ($0.01) per share and five million (5,000,000)
                  shares shall be preferred stock with the par value of one cent
                  ($0.01) per share."

                  RESOLVED FURTHER, that Article XV of the amended and restated
         Certificate of Incorporation is hereby deleted in its entirety.

         SECOND: That thereafter, pursuant to resolution of its Board of
Directors, an annual meeting of the Stockholders of the Corporation was duly
called and held, upon notice in accordance with Section 222 of the General
Corporation Law of the State of Delaware at which meeting the necessary number
of shares as required by statute were voted in favor of the amendment.

         THIRD: That said amendments were duly adopted in accordance with the
provisions of Section 242 of the General Corporation Law of the State of
Delaware.
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         The Corporation has caused this Certificate to be executed by Steven G.
Bunger, its President, and by Lawrence Trachtenberg, its Secretary, as of July
20, 2000.

                                             MOBILE MINI, INC.


                                             By:  /s/ Steven G. Bunger
                                                  Steven G. Bunger, President

ATTEST:

/s/ Lawrence Trachtenberg
Lawrence Trachtenberg, Secretary