There is hereby established in the United States Treasury, pursuant to section 3535(f) of this title, a working capital fund for the Department of Housing and Urban Development (referred to in this paragraph as the "Fund"): Provided, That amounts transferred to the Fund under this heading shall be available for Federal shared services used by offices and agencies of the Department, and for such portion of any office or agency's printing, records management, space renovation, furniture, or supply services as the Secretary determines shall be derived from centralized sources made available by the Department to all offices and agencies and funded through the Fund: Provided further, That of the amounts made available in this title ¹ for salaries and expenses under the headings "Executive Offices", "Administrative Support Offices", "Program Office Salaries and Expenses", and "Government National Mortgage Association", the Secretary shall transfer to the Fund such amounts, to remain available until expended, as are necessary to fund services, specified in the first proviso, for which the appropriation would otherwise have been available, and may transfer not to exceed an additional $10,000,000, in aggregate, from all such appropriations, to be merged with the Fund and to remain available until expended for use for any office or agency: Provided further, That amounts in the Fund shall be the only amounts available to each office or agency of the Department for the services, or portion of services, specified in the first proviso: Provided further, That with respect to the Fund, the authorities and conditions under this heading shall supplant the authorities and conditions provided under section 3535(f) of this title.