(a) The Department of Veterans Affairs may at any time advance any sum or sums as are reasonably necessary and proper for the maintenance, repair, alteration, or improvement of the security for a loan or for the payment of taxes, assessments, ground or water rights, or casualty insurance thereon: Provided, That no advance shall be made for alterations or improvements which are not necessary for the maintenance or repair of the security if such advance will increase the indebtedness to an amount in excess of $33,000.

(b) All sums disbursed incident to the making of advances under this section shall be added to the indebtedness. Department of Veterans Affairs may require any such advances to be secured ratably and on a parity with the principal indebtedness, or otherwise secured. The sum so advanced shall be evidenced by a supplemental note or otherwise as may be required by Department of Veterans Affairs.

(c) Department of Veterans Affairs may pay and charge against the indebtedness, or against the proceeds of the sale of any security therefor, any expense which is reasonably necessary for collection of the debt, protection, repossession, preservation, or liquidation of the security or of the lien thereon, including a reasonable amount for trustees' and legal fees.

(d) The Department of Veterans Affairs may treat as an advance and add to the mortgage balance the one-half of one percent funding fee due on a transfer under 38 U.S.C. 3714 when this is not paid at the time of transfer.