Cal. Civil Code - CIV § 1812.10. Section 1812.10.
(a)
An action on a contract or installment account under this chapter shall be tried in the superior court in the county where the contract was in fact signed by the buyer, where the buyer resided at the time the contract was entered into, where the buyer resides at the commencement of the action, or where the goods purchased pursuant to the contract have been so affixed to real property as to become a part of that real property.
(b)
In the superior court designated as
the proper court in subdivision (a), the proper court location for trial of an action under this chapter is the location where the court tries that type of action that is nearest or most accessible to where the contract was in fact signed by the buyer, where the buyer resided at the time the contract was entered into, where the buyer resides at the commencement of the action, or where the goods purchased pursuant to the contract have been so affixed to real property as to become a part of that real property. Otherwise, any location of the superior court designated as the proper court in subdivision (a) is the proper court location for the trial of the action. The court may specify by local rule the nearest or most accessible court location where the court tries that type of case.
(c)
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 superior court and court location described in this section as a proper place for the trial of the action. Those facts may be stated in a verified complaint and shall not be stated on information or belief. When that affidavit is filed with the complaint, a copy thereof shall be served with the summons. If a plaintiff fails to file the affidavit or state facts in a verified complaint required by this section, no further proceedings may occur, but the court shall, upon its own motion or upon motion of any party, dismiss the action without prejudice. The court may, on terms that are just, permit the affidavit to be filed subsequent to the filing of the complaint and a copy of the affidavit shall be served on the defendant. The time to answer or otherwise plead shall date from that service.