Cal. Bus. & Prof. Code § 5492
For purposes of compliance with Section 5491, fair and just compensation is presumed to be paid upon the payment of the fair market value of the on-premises advertising display as of the date written notice is given to the owner of the display requiring conformance or removal thereof.
Fair market value consists of the actual cost of removal for the display, the actual cost to repair any damage caused to the real property or improvements thereon as a result of the removal of the display, and the actual cost to duplicate the advertising display required to be removed as of the date written notice requiring removal for nonconformance is given to the owner by the governmental body requiring conformance or removal.
Ca. Bus. and Prof'l. Code § 5492