The head of a Federal agency, as soon as practicable after the date of payment of the purchase price or the date of deposit in court of funds to satisfy the award of compensation in a condemnation proceeding to acquire real property, whichever is the earlier, shall reimburse the owner, to the extent the head of such agency deems fair and reasonable, for expenses he necessarily incurred for—

(1) recording fees, transfer taxes, and similar expenses incidental to conveying such real property to the United States;

(2) penalty costs for prepayment of any preexisting recorded mortgage entered into in good faith encumbering such real property; and

(3) the pro rata portion of real property taxes paid which are allocable to a period subsequent to the date of vesting title in the United States, or the effective date of possession of such real property by the United States, whichever is the earlier.