Any municipality issuing revenue bonds pursuant to the authority granted in Section 21-27-23 shall install and maintain proper books of record and account (separate entirely from other records and accounts of such municipality), in which correct entries shall be made of all dealings or transactions of or in relation to the properties, business and affairs of the system or combined system. The governing authorities of such municipality, not later than three months after the close of any calendar, operating or fiscal year, shall cause to be prepared a balance sheet and an income and operating and surplus account showing, respectively, in reasonable detail, the financial condition of the system or combined system at the close of such preceding calendar, operating or fiscal year, and the financial operations thereof during such year. Said balance sheet and the income and operating and surplus account shall at all times during the usual business hours be open to examination and inspection by any taxpayer, user of the services furnished by the system, or any holder of bonds issued pursuant to the authority granted in Section 21-27-23, or any one acting for or on behalf of such taxpayer, user of the services of the system, or bondholder.