Addendum Nr. 1 to the Undertaking to Subscribe to New Profit Certificates of 27 February 2001 and Addendum Nr. 4 tothe Joint Venture Agreement of 8 October 1999

Exhibit 10.45

Addendum Nr. 1 to the Undertaking to Subscribe to New Profit Certificates

of 27 February 2001

and

Addendum Nr. 4 to the Joint Venture Agreement of 8 October 1999

Between:

represented for the purpose of this Addendum by Mr. Charles Barbo,

hereinafter referred to as “Shurgard”;

represented for the purpose of this Addendum by Mr. Harrell Beck,

hereinafter referred to as “SSC Benelux Inc.”;

registered with the Register of Legal Entities under the number 0454.737.186,

represented for the purpose of this Addendum by Mr. Harrell Beck and Mr. Charles Barbo,

hereinafter referred to as “Shurope”;

registered with the Register of Legal Entities under the number 0460.156.617,

represented for the purpose of this Addendum by Mr. Dave Grant, Manager,

hereinafter referred to as “Recom & Co”;

represented for the purpose of this Addendum by Mr. Frederick P. Zarrilli,

hereinafter referred to as “Fremont GP”;

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represented for the purpose of this Addendum by Mr. Claude J. Zinngrabe,

hereinafter referred to as “Fremont LP”;

represented for the purpose of this Addendum by Mr. Matthew J. Reidy,

hereinafter referred to as “Fremont SE GP”;

represented for the purpose of this Addendum by Mr. Claude J. Zinngrabe, hereinafter referred to as “Fremont SE LP”;

represented for the purpose of this Addendum by Mr. Claude J. Zinngrabe, hereinafter referred to as “Fll”;

And:

registered with the Register of Legal Entities under the number 0454.057.394,

represented for the purpose of this Addendum by SSC Benelux Inc., Executive Manger, represented by Dave Grant,

hereinafter referred to as the “Company”.

Whereas:

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NOW, THEREFORE, the Parties hereto agree as follows:

Unless otherwise defined herein, any word in this Addendum starting with a capital letter is a defined term and should, with respect to Articles 2 and 9 hereof, have the same meaning as in the NPC Agreement, and with respect to Articles 3, 4, 5, 6, 7 and 8 hereof have the same meaning as in the JV Agreement.

The Parties agree that the amendment of the Credit Agreement pursuant to the Supplemental Agreement shall be deemed to consitute an event as set out in Article 4.4, paragraph six, (i) of the NPC Agreement.

In view of the fact that no calls have been made on the New Profit Certificates, the New Profit Certificates are automatically annulled, with loss of all rights and obligations attached thereto, as a result of the Supplemental Agreement, which constitutes the full and final reimbursement of the Restated Required Facility.

““COMPANY” shall mean Shurgard Self Storage SCA (f/k/a SSC Benelux & Co S.C.A.), a “société en commandite par actions / commanditaire vennootschap op aandelen” organised under the laws of Belgium, having its registered office at Quai du Commerce/Handelskaai 48, 1000 Brussels, and registered with the Register of

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Legal Entities under the number 0454.057.394. At Closing the charter of the Company shall be modified to conform to the text of Exhibit A to this Agreement;”

““EXISTING PARTNERS” shall mean Shurgard, SSC Benelux, Shurope and Recom & Co;”

““REQUIRED FACILITY” shall mean the Euro 140,000,000 revolving credit agreement relating to the development of self storage centres by Shurgard Self Storage SCA Group entered into on or around October 4, 1999 between SSC Benelux & Co. SCA (former name of Shurgard Self Storage SCA), the companies defined therein as Original Charging Companies, Credit Suisse First Boston (Europe) Limited as Arranger, Credit Suisse First Boston, London branch as Agent and Security Trustee and the financial institutions named therein as Banks;”

““UNDERTAKING TO SUBSCRIBE” shall mean the agreement with respect to the undertaking to subscribe to New Profit Certificates entered into on 27 February 2001, as amended;”

The following text shall be added at the end of Article 4.2 of the JV Agreement and shall replace the text added to Article 4.2 pursuant to Addendum Nr. 3 to the JV Agreement:

“As a result of (i) the sale by Deutsche Bank GP to SSC Benelux Inc. of its 7 General Partner Interests in the Company, (ii) the sale by AIG GP to SSC Benelux Inc. of its 4 General Partner Interests in the Company, and, (iii) the sale by ESS to SSC Benelux Inc. of its 4 General Partner Interests in the Company the General Partner Interests owned by the Parties as of the closing of such sales are as follows:

The following text shall be added after the second paragraph of Article 4.3 of the JV Agreement:

“As a result of (i) the conversion of 136,111 Warrants (3 Warrants held by ESS; 4 Warrants held by SSC Benelux; 592 Warrants held by Grana; 6,371 Warrants held by Shurope and 129,141 Warrants held by Recom & Co) into 136,111 Class A Limited Liability Partner Interests in the Company on 8 September 2003, and (ii) the sale by Grana to SSC Benelux

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Inc. of its 1,017 Class A Limited Liability Partner Interests in the Company, and, (iii) the sale by ESS to SSC Benelux Inc. of its 3 Class A Limited Liability Partner Interests in the Company,    , the Class A Limited Liability Partner Interests owned by the Parties as of the closing of such sales are as follows:

The following text shall be added at the end of Article 4.6.1 of the JV Agreement and shall replace the text added to Article 4.6.1 pursuant to Addendum Nr. 3 to the JV Agreement:

“As a result of (i) the sale by Deutsche Bank LLP to SSC Benelux Inc. of its 52,165 Profit Certificates and 5,225 New Profit Certificates, (ii) the sale by AIG LLP to SSC Benelux Inc. of its 21,922 Profit Certificates and 2,177 New Profit Certificates, (iii) the sale by AIRE to SSC Benelux Inc. of its 7,308 Profit Certificates and 726 New Profit Certificates, (iv) the sale by Grana to SSC Benelux Inc. of its 101 New Profit Certificates and (v) the annulment of the New Profit Certificates, the Profit Certificates owned by the Parties as of the closing of such sale will be as follows:

The New Profit Certificates have been annulled.”

“The physical persons representing the General Partner Investors at the Board of Managers of the Company shall be:

“SSC Benelux Inc. shall be represented by the following individuals:

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Such persons shall represent SSC Benelux Inc. and vote as 1 block having jointly 28 votes.

ESS shall be represented by Ake Fogelberg and Patrick Metdepenninghen. They shall both represent ESS and vote as 1 block having jointly 4 votes.”

“If to the Existing Partners

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SSC Benelux Inc., Shurope, Recom & Co, Fremont GP, Fremont LP, Fremont SE GP and Fremont SE LP shall cause the Board of Managers of the Company (i) to convene an Extraordinary Partners’ Meeting as soon as practical following the signing date of this Addendum to establish the annulment of the New Profit Certificates in a notarial deed and to amend the bylaws of the Company accordingly, and (ii) to vote affirmative at such Extraordinary Partners’ Meeting on the proposals in this respect.

SSC Benelux Inc., Shurope, Recom & Co, Fremont GP, Fremont LP, Fremont SE GP and Fremont SE LP also undertake to vote in such way as to modify the Charter of the Company in accordance with the above modifications to the JV Agreement, if and to the extent necessary, substantially in the form as attached hereto as Schedule 1.

This Addendum shall be governed by Belgian law.

All disputes arising out of or in connection with this Addendum shall be resolved in accordance with the provisions of Article 14.8 of the JV Agreement.

Made on                      2004, in nine originals. Each of Party acknowledges receipt of its own original.

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