Whenever real property is acquired by a State agency and furnished as a required contribution incident to a Federal program or project, the Federal agency having authority over the program or project may not accept such property unless such State agency has made all payments and provided all assistance and assurances, as are required of a State agency by sections 4630 and 4655 of this title. Such State agency shall pay the cost of such requirements in the same manner and to the same extent as the real property acquired for such project, except that in the case of any real property acquisition or displacement occurring prior to July 1, 1972, such Federal agency shall pay 100 per centum of the first $25,000 of the cost of providing such payments and assistance.

Whenever real property is acquired by a State agency at the request of a Federal agency for a Federal program or project, such acquisition shall, for the purposes of this chapter, be deemed an acquisition by the Federal agency having authority over such program or project.

Whenever real property is acquired by the government of the District of Columbia or the Washington Metropolitan Area Transit Authority for a program or project which is not subject to sections 4630 and 4631 of this title, and such acquisition will result in the displacement of any person on or after January 2, 1971, the Mayor of the District of Columbia or the Washington Metropolitan Area Transit Authority, as the case may be, shall make all relocation payments and provide all assistance required of a Federal agency by this chapter. Whenever real property is acquired for such a program or project on or after such effective date, such Mayor or Authority, as the case may be, shall make all payments and meet all requirements prescribed for a Federal agency by subchapter III of this chapter.

In order to prevent unnecessary expenses and duplications of functions, and to promote uniform and effective administration of relocation assistance programs for displaced persons under sections 4626, 4630, and 4635 of this title, a State agency may enter into contracts with any individual, firm, association, or corporation for services in connection with such programs, or may carry out its functions under this subchapter through any Federal or State governmental agency or instrumentality having an established organization for conducting relocation assistance programs. Such State agency shall, in carrying out the relocation assistance activities described in section 4626 of this title, whenever practicable, utilize the services of State or local housing agencies, or other agencies having experience in the administration or conduct of similar housing assistance activities.

In order to encourage and facilitate the construction or rehabilitation of housing to meet the needs of displaced persons who are displaced from dwellings because of any Federal or Federal financially assisted project, the head of the Federal agency administering such project is authorized to make loans as a part of the cost of any such project, or to approve loans as a part of the cost of any such project receiving Federal financial assistance, to nonprofit, limited dividend, or cooperative organizations or to public bodies, for necessary and reasonable expenses, prior to construction, for planning and obtaining federally insured mortgage financing for the rehabilitation or construction of housing for such displaced persons. Notwithstanding the preceding sentence, or any other law, such loans shall be available for not to exceed 80 per centum of the reasonable costs expected to be incurred in planning, and in obtaining financing for, such housing, prior to the availability of such financing, including, but not limited to, preliminary surveys and analyses of market needs, preliminary site engineering, preliminary architectural fees, site acquisition, application and mortgage commitment fees, and construction loan fees and discounts. Loans to an organization established for profit shall bear interest at a market rate established by the head of such Federal agency. All other loans shall be without interest. Such Federal agency head shall require repayment of loans made under this section, under such terms and conditions as he may require, upon completion of the project or sooner, and except in the case of a loan to an organization established for profit, may cancel any part or all of a loan if he determines that a permanent loan to finance the rehabilitation or the construction of such housing cannot be obtained in an amount adequate for repayment of such loan. Upon repayment of any such loan, the Federal share of the sum repaid shall be credited to the account from which such loan was made, unless the Secretary of the Treasury determines that such account is no longer in existence, in which case such sum shall be returned to the Treasury and credited to miscellaneous receipts.

No payment received under this subchapter shall be considered as income for the purposes of title 26; or for the purposes of determining the eligibility or the extent of eligibility of any person for assistance under the Social Security Act [42 U.S.C. 301 et seq.] or any other Federal law (except for any Federal law providing low-income housing assistance).

The Administrator of General Services is authorized to transfer to a State agency for the purpose of providing replacement housing required by this subchapter, any real property surplus to the needs of the United States within the meaning of chapters 1 to 11 of title 40 and division C (except sections 3302, 3307(e), 3501(b), 3509, 3906, 4710, and 4711) of subtitle I of title 41. Such transfer shall be subject to such terms and conditions as the Administrator determines necessary to protect the interests of the United States and may be made without monetary consideration, except that such State agency shall pay to the United States all net amounts received by such agency from any sale, lease, or other disposition of such property for such housing.