Cal. Civ. Code § 1780
(a) Any consumer who suffers any damage as a result of the use or employment by any person of a method, act, or practice declared to be unlawful by Section 1770 may bring an action against that person to recover or obtain any of the following:
(b)
(1) Any consumer who is a senior citizen or a disabled person, as defined in subdivisions (f) and (g) of Section 1761, as part of an action under subdivision (a), may seek and be awarded, in addition to the remedies specified therein, up to five thousand dollars ($5,000) where the trier of fact does all of the following:
(d) An action under subdivision (a) or (b) may be commenced in the county in which the person against whom it is brought resides, has his or her principal place of business, or is doing business, or in the county where the transaction or any substantial portion thereof occurred.
In any action subject to this section, concurrently with the filing of the complaint, the plaintiff shall file an affidavit stating facts showing that the action has been commenced in a county described in this section as a proper place for the trial of the action. If a plaintiff fails to file the affidavit required by this section, the court shall, upon its own motion or upon motion of any party, dismiss the action without prejudice.