A county board of supervisors may, by ordinance, provide for and regulate the sale of advertising space on county real or personal property, for the sole purpose of raising revenue for the county. Any such advertising shall comply with the provisions of Chapter 2 (commencing with Section 5200) of Division 3 of the Business and Professions Code. Nothing in this section shall be construed to empower a county to place or maintain an advertising structure, as defined in Section 5203 of the Business and Professions Code.
Ca. Gov. Code § 26109