Cal. Bus. & Prof. Code § 7163

(a) No contract for home improvement shall be enforceable against the buyer if the obtaining of a loan for all or a portion of the contract price is a condition precedent to the contract or if the contractor provides financing, or in any manner assists the buyer to obtain a loan or refers the buyer to any person who may loan or arrange a loan for all or a portion of the contract price unless all of the following requirements are satisfied:
1. (1) The third party, if any, agrees to make the loan.
2. (2) The buyer agrees to accept the loan or financing.
3. (3) The buyer does not rescind the loan or financing transaction, within the period prescribed for rescission, pursuant to the federal Truth in Lending Act (15 U.S.C. Sec. 1601 et seq.) or Regulation Z, if applicable.
(b) Until the requirements of paragraphs (1), (2), and (3) of subdivision (a) are satisfied, it shall be unlawful for the contractor to do any of the following:
1. (1) Deliver any property or perform any services other than obtaining building permits or other similar services preliminary to the commencement of the home improvement for which no mechanic’s lien can be claimed.
2. (2) Represent in any manner that the contract is enforceable or that the buyer has any obligation thereunder.
  Any violation of this subdivision shall render the contract unenforceable.
(c) If the contract is unenforceable pursuant to subdivision (a) or subdivision (b), the contractor shall immediately and without condition return all money, property, and other consideration given by the buyer. If the buyer gave any property as consideration and the contractor does not or cannot return it for whatever reason, the contractor shall immediately return the fair market value of the property or its value as designated in the contract, whichever is greater. Nothing herein shall prohibit a contractor from receiving a downpayment otherwise permitted by law provided the contractor returns the downpayment as herein required if the contract is unenforceable pursuant to subdivision (a) or (b).
(d)
1. (1) Except as provided in paragraph (2), the buyer may retain without obligation in law or equity any services or property provided pursuant to a contract that is unenforceable pursuant to subdivision (a) or subdivision (b).
2. (2) If the contractor has delivered any property to the buyer pursuant to a contract which is unenforceable pursuant to subdivision (a) or subdivision (b), the buyer shall make the property available to the contractor for return provided that all of the following requirements are satisfied:
  1. (A) The property can be practically returned to the contractor without causing any damage to the buyer.
  2. (B) The contractor, at the contractor’s expense, first returns to the buyer any money, property, and other consideration taken by the contractor provided that the property is returned in the condition that it was in immediately prior to its taking. If applicable, the contractor shall also, at its expense, reinstall any property taken in the manner in which the property had been installed prior to its taking.
  3. (C) The contractor, at the contractor’s expense, picks up the property within 60 days of the execution of the contract.
(e) For the purpose of this section, “home improvement” means “home improvement” as defined in Section 7151. Goods are included within the definition notwithstanding whether they are to be attached to real property or to be so affixed to real property as to become a part thereof whether or not severable therefrom.
(f) The rights and remedies provided the buyer under this section are nonexclusive and cumulative to all other rights and remedies under other laws.
(g) Any waiver of this section shall be deemed contrary to public policy and shall be void and unenforceable. However, the buyer may waive subdivisions (a) and (b) to the extent that the contract is executed in connection with the making of emergency repairs or services that are necessary for the immediate protection of persons or real or personal property. The buyer’s waiver for emergency repairs or services shall be in a dated written statement that describes the emergency, states that the contractor has informed the buyer of subdivisions (a) and (b) and that the buyer waives those provisions, and is signed by each owner of the property. Waivers made on printed forms are void and unenforceable.