Cal. Bus. & Prof. Code § 7032
Nothing in this chapter shall limit the power of a city or county to regulate the quality and character of installations made by contractors through a system of permits and inspections which are designed to secure compliance with and aid in the enforcement of applicable state and local building laws, or to enforce other local laws necessary for the protection of the public health and safety. Nothing in this chapter shall limit the power of a city or county to adopt any system of permits requiring submission to and approval by the city or county of plans and specifications for an installation prior to the commencement of construction of the installation.
Cities or counties may direct complaints to the registrar against licensees based upon determinations by city or county enforcement officers of violations by such licensees of codes the enforcement of which is the responsibility of the complaining city or county. Such complaints shall to the extent determined to be necessary by the registrar be given priority in processing over other complaints.
Nothing contained in this section shall be construed as authorizing a city or county to enact regulations relating to the qualifications necessary to engage in the business of contracting.
Ca. Bus. and Prof'l. Code § 7032