Residential building lots shall contain at least 40 feet of lot frontage abutting on a public right-of-way. When in the public interest and not solely for the interest of the applicant, the Planning and Zoning Commission shall review for appropriateness two or three residential adjacent building lots that share a common driveway. Two residential adjacent building lots that share a common driveway may each have 30 feet of lot frontage abutting on a public right-of-way. A limit of three residential adjacent building lots sharing a common driveway may each have 25 feet of lot frontage abutting a public right-of-way. Common driveways which serve two or three lots shall have a minimum width of 16 ft. Four or more lots are not permitted to have a common driveway.