One temporary real estate sign not over 16 square feet in area, attached to a building or freestanding, may be erected in the C-1, C-2, C-3, I, ED and VC Zones, and on the premises of a conforming commercial use, excluding home occupations, in any zone, without a permit advertising the sale, lease or rental of the premises upon which the sign is located, except that a lot or building with frontage on two public ways may have one sixteen-square-foot sign on each public way, and shall be removed by the owner or agent of the owner within 10 days of said sale, lease or rental. In addition, conforming existing wall and freestanding signs affixed to the premises may advertise the sale, lease, or rental of the premises upon which the sign is located. Such advertising shall be removed by the owner or agent of the owner within 10 days of said sale, lease or rental.