Cal. VEH § 11709

(a) A dealer’s established place of business, and other sites or locations as may be operated and maintained by the dealer in conjunction with his or her established place of business, shall have posted, in a place conspicuous to the public in each and every location, the license, or a true and exact copy of the license, issued by the department to the dealer and to each salesperson employed by the dealer and shall have erected or posted thereon signs or devices providing information relating to the dealer’s name and the location and address of the dealer’s established place of business to enable any person doing business with the dealer to identify him or her properly. A sign erected or posted pursuant to this subdivision, on an established place of business, shall have an area of not less than two square feet per side displayed and shall contain lettering of sufficient size to enable the sign to be read from a distance of at least 50 feet. This section shall not apply to a dealer who is a wholesaler involved for profit only in the sale of vehicles between licensed dealers.

(b) Notwithstanding Section 11704 and this section, a dealer may display vehicles at a fair, exposition, or similar exhibit without securing a branch license, if no actual sales are made at those events and the display does not exceed 30 days.

(c) A vehicle displayed pursuant to subdivision (b) or (e) shall be identified by a sign or device providing information relating to the dealer’s name and the location and address of the dealer’s established place of business.

(d) This section shall not be applicable to a dealer who deals only in off-highway vehicles subject to identification, as defined in Section 38012.

(e) Notwithstanding Section 11704 and this section, a vessel dealer may display a trailer and may sell a trailer in conjunction with the sale of a vessel at a fair, exposition, or similar exhibit without securing a branch license if the display does not exceed 30 days.