The license taxes established pursuant to Section 15.20.020 shall be due and payable at the City Hall, Montague, California, upon issuance of a building permit for the installation of a mobile home; provided, however, that there shall be a refund of such taxes in the event that the building permit is not used for such installation. There shall be no refund after commencement. (Ord. 176 § 2, 1981)