All off-street parking areas for other than dwellings as defined by this Chapter providing capacity for more than two (2) vehicles, other than within a building, shall be permanently screened from any adjoining property or property lying across a street or alley from said parking area which is zoned for Districts "R-1" to "R-4", inclusive, by a solid wall, fence, and/or screen planting sufficiently thick to serve the purpose of a solid screen; and said screening shall be not less than six (6) feet in height or greater if warranted by height of vehicle to be screened, elevation differences between properties, etc., as determined by the City. Such screening shall be maintained in good condition. See Section 500.030, "Development Standards", for additional requirements.