The governing body of any county, city, or town which has adopted ordinances under the provisions of Chapter 22 (§ 15.2-2200 et seq.) of Title 15.2, may require as a part of such land use regulations for residential subdivisions employing roadways and parking areas not in public ownership, the posting and maintenance of signs or other appropriate markings regulating the operation and parking of motor vehicles and pedestrian traffic, and may adopt ordinances applying the regulations to existing and future residential subdivisions.