(a) The municipality by ordinance or the county by order may provide that the tax is imposed at a flat amount on each parked motor vehicle or is imposed as a percentage of the amount charged for event parking by the owner or lessee of the parking facility.
(b) Regardless of the method of imposition, the amount of the tax may not exceed $3 for each motor vehicle, except as provided by Subsection (b-1).

(b-1) A municipality with a population of more than 700,000 within a county with a population of more than 2.1 million adjacent to a county with a population of more than 2.5 million may impose the tax authorized by this subchapter at a rate not to exceed $5 for each motor vehicle.
(c) The ballot proposition at the election held to adopt the tax must specify the maximum rate of the tax to be adopted.
(d) The municipality by ordinance or the county by order may repeal or decrease the rate of the tax imposed under this section.