Supplementary parking regulations in MR Multiple-Family Residence Districts. In MR Multiple-Family Residence Districts, wherever space is provided for the parking of 10 or more vehicles in the open, such spaces shall be individually identified by means of pavement markings. No parking space shall be located in any front yard or within 10 feet of any lot line in side or rear yards. The parking of motor vehicles within 15 feet of any wall or portion thereof of a two-or-more-family dwelling, which wall contains windows other than bathroom or kitchen windows with a sill height of less than eight feet above the level of the said parking space, is prohibited. No service of any kind shall be permitted to be extended to users of the lot, including automobile service, repair or fueling, and no gasoline, oil, grease or other supplies shall be stored or sold in any such lot or in any garage on such lot. Parking areas shall be screened by a substantial hedge, wall or fence as approved by the Planning Board.