Common examples of group developments include six-unit apartment buildings, apartment complexes, condominium complexes, strip centers, shopping centers and office centers. (One-tenant office or commercial buildings containing less than 5,000 square feet of gross floor area, four-unit apartment buildings, and other land uses in which each nonresidential building contains only one tenant, or where the lot contains only one structure, or where each residential building contains four or fewer dwelling units, are not group developments even though such developments may contain parcels under common ownership.)