The proceeds derived from the sale of any bonds issued pursuant to this chapter must be paid to the county treasurer, to be deposited in a separate bond account fund, and must be expanded from time to time and made use of as follows:

(a) Any accrued interest must be applied to the payment of the first installment of interest to become due to such bonds.

(b) Any premium must be applied to the payment of the first installment of principal of such bonds.

(c) The remaining proceeds must be expended, upon the warrant or order of the governing body, for the following purposes:

(1) To defray the costs of issuing the bonds authorized by this chapter;

(2) To pay interest on such bonds for a period of not exceeding two years; and

(3) To provide for fire protection services for the county.

(d) If, after the final completion of any fire protection system, the governing body shall certify to the county treasurer that any remaining balance in the bond account is no longer needed for its fire protection program, then the balance must be held by the treasurer and used to effect the retirement of bonds then outstanding, which have been issued pursuant to this chapter. Provided, however, that the purchaser of the bonds is not responsible for the proper application of the proceeds to the purposes for which the bonds are issued.