In the event the council grants a variance from this title for any commercial building, such variance shall be granted by a permit which may be revoked at any time. No construction or expenditure of money or any other action in reliance on any such permit shall be deemed to vest any right pursuant to any such permit. Such permit may be granted subject to any conditions which appear appropriate to the council. Without obtaining prior authorization from the council, no person shall modify any structure subject to any such permit, excepting only routine maintenance such as painting or other resurfacing, or other repair which restores the structure to the original condition for which the permit was issued. (Prior code § 9.21.705)