Bond proceeds shall be used only to pay the cost of infrastructure improvements, including:
(1) the cost of establishing, acquiring, designing, constructing, extending, or altering infrastructure improvements;
(2) the cost of issuing bonds;
(3) payment of the principal of and interest on loans, money advances, or indebtedness incurred by the county for any purpose stated in § 21–504(a) of this subtitle, including refunding bonds previously issued; and
(4) funding of a debt service reserve fund or payment of interest before, during, or for a limited period of time after constructing the infrastructure improvements.