Flags, emblems or other insignia of a nation, state, county, municipality, school, business, or religious group, provided that no more than one such flag, emblem or insignia shall be permitted for each entity, and that no such individual display exceed 24 square feet in area. No more than three flags or similar displays shall be permitted on the property. These regulations shall not apply to flags of the United States of America, or to permitted home office uses.