42 U.S.C. § 4653: Expenses incidental to transfer of title to United States

recording fees, transfer taxes, and similar expenses incidental to conveying such real property to the United States; penalty costs for prepayment of any preexisting recorded mortgage entered into in good faith encumbering such real property; and 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.