Notwithstanding any of the provisions of this subchapter, the Secretary is authorized, upon application by the mortgagee, to insure or to make commitments to insure under section 1738 or any mortgage executed in connection with the sale by the Government, or any agency or official thereof, of any housing acquired or constructed under Public Law 849, Seventy-sixth Congress, as amended; Public Law 781, Seventy-sixth Congress, as amended; or Public Laws 9, 73, or 353, Seventy-seventh Congress, as amended (including any property acquired, held or constructed in connection with such housing or to serve the inhabitants thereof), without regard to—

((1)) any limit as to the time when any mortgage may be insured under this subchapter;

((2)) any limit as to the aggregate amount of principal obligations of all mortgages insured under this subchapter, but the aggregate amount of principal obligations of all mortgages insured pursuant to this section shall not exceed $750,000,000;

((3)) any requirement that the obligation be approved for mortgage insurance prior to the beginning of construction or that the construction be new construction;

((4)) any of the provisions of subsections (b)(2) or (b)(5) of or paragraphs (B) and (C) of the first sentence of :