California Code, Civil Code - CIV § 1807.3

(a) If any payment, other than a deferred downpayment, under a contract or refinancing agreement is more than twice the amount of an otherwise regularly scheduled equal payment, the contract or refinancing agreement shall contain the following provision:

(b) If the buyer defaults in the payment of any balloon payment, he or she shall be given an absolute right to obtain a new payment schedule. Unless agreed to by the buyer, the periodic payments under the new schedule shall not be substantially greater than the average of the preceding installments.