Bonds of such city may be issued and sold to pay the cost of the lands acquired and the cost of such improvements. The bonds shall be payable in not to exceed 10 annual installments. The last installment shall be not later than 12 years from the date of issuance of such bonds. The bonds shall bear interest at a rate not to exceed the maximum rate of interest prescribed by Kan. Stat. Ann. § 10-1009, and amendments thereto.