California Code, Business and Professions Code - BPC § 10244

Any loan made by any person and secured directly by a lien on real property, other than a note given back to the seller by the purchaser on account of the purchase price, which provides for installment payments and the term of which is less than three years, shall require substantially equal installment payments over the period of the loan with the final payment not payable until the maturity date thereof. No installment including the final installment shall be greater than twice the amount of the smallest installment.

If any loan having an original maturity period of less than three (3) years is renewed or refinanced, the total amount of charges to be paid on both the original obligation and the balance of such obligation, as renewed or refinanced, shall not in the aggregate exceed the amount of charges as provided in Section 10242, and if such a loan is renewed or refinanced through the person who negotiated the original loan, the total amount of costs and expenses to be paid on both the original obligation and the renewed or refinanced obligation shall not exceed in the aggregate the amount of costs and expenses authorized in subdivision (a) of said section.

The provisions of this section do not apply to a bona fide loan, secured by a first trust deed on real property, made in connection with the financing of the usual costs of the development of a residential, commercial or industrial building or buildings on the property under a written agreement providing for the disbursement of the loan funds as costs are incurred or in relation to the progress of the work and providing for title insurance insuring the priority of the security as against mechanic's and materialmen's liens or for the final disbursement of at least ten (10) percent of the loan funds after the expiration of the period for the filing of mechanics and materialmen's liens.