The residential construction tax herein required to be paid shall be due and payable upon issuance by the city of a building permit for the construction of any residential dwelling unit, or upon issuance by the city or other appropriate governmental agency of a permit to construct and install electrical and plumbing equipment to service a mobilehome lot in a mobilehome park; provided, however, that there shall be refund of such tax to the person who paid such tax in the event that the building permit or permit to construct and install electrical and plumbing equipment to service a mobilehome lot in a mobilehome park expires within the meaning of Section 302(d) of the Uniform Building Code, 1970 Edition, Volume I, and within thirty (30) days following the date of such expiration written application for such refund is made by the person who paid such tax setting forth in full the facts showing that such permit has expired. (Prior code § 41.07.079)