Cal. Gov. Code § 25526.5
Whenever the board of supervisors determines that any real property or interest therein belonging to the county is no longer necessary for county or other public purposes, and its estimated value does not exceed twenty-five thousand dollars ($25,000), the county may sell, exchange, quitclaim, or convey that real property or interest therein in the manner and upon the terms and conditions approved by the board of supervisors without complying with any other sections in this article. The board of supervisors may, by ordinance, designate an appropriate county officer or officers to execute sales of the real property or interest therein, provided that notice of intention that the county officer or officers will execute the sale shall be posted in a public place for five working days prior to effecting the transfer.
Ca. Gov. Code § 25526.5