Commercial uses which shall be limited to not more than six service-type stores such as food markets, variety and sundry shops, barbershops or beauty parlor, meat market, kosher food purveyor, coffee shop, and the like, which commercial usage shall be situated in existing public buildings or replacements thereof or in unit rental buildings hereinafter described; additionally, there may be constructed up to two buildings containing units for rental, with no advertising signs on or about the premises relating thereto, which shall contain a maximum of 50 rental units for rental by day, week, or month to relatives, friends, neighbors, associates, persons in some fashion related to occupants of the development and not solicited off the streets or the highways.