this paragraph, $41,400,000, to remain available until expended: Provided , That of the funds made available under this heading, $19,400,000, shall be available for rural housing vouchers to any low-income household (including those not receiving rental assistance) residing in a property financed with a section 515 loan which has been prepaid after September 30, 2005: Provided further , That the amount of such voucher shall be the difference between comparable market rent for the section 515 unit and the tenant paid rent for such unit: Provided further , That funds made available for such vouchers shall be subject to the availability of annual appropriations: Provided further , That the Secretary shall, to the maximum extent practicable, administer such vouchers with current regulations and administrative guidance applicable to section 8 housing vouchers administered by the Secretary of the Department of Housing and Urban Development: Provided further , That if the Secretary determines that the amount made available for vouchers in this or any other Act is not needed for vouchers, the Secretary may use such funds for the demonstration program for the preservation and revitalization of multi-family rental housing properties described in this paragraph: Provided further , That of the funds made available under this heading, $22,000,000 shall be available for a demonstration program for the preservation and revitalization of the sections 514, 515, and 516 multi-family rental housing properties to restructure existing USDA multi-family housing loans, as the Secretary deems appropriate, expressly for the purposes of ensuring the project has sufficient resources to preserve the project for the purpose of providing safe and affordable housing for low-income residents and farm laborers including reducing or eliminating interest