California Code, Vehicle Code - VEH § 11709.2

Every dealer shall conspicuously display a notice, not less than eight inches high and 10 inches wide, in each sales office and sales cubicle of a dealer's established place of business where written terms of specific sale or lease transactions are discussed with prospective purchasers or lessees, and in each room of a dealer's established place of business where sale and lease contracts are regularly executed, which states the following:

California law does not provide for a “cooling-off” or other cancellation period for vehicle lease or purchase contracts. Therefore, you cannot later cancel such a contract simply because you change your mind, decide the vehicle costs too much, or wish you had acquired a different vehicle. After you sign a motor vehicle purchase or lease contract, it may only be canceled with the agreement of the seller or lessor or for legal cause, such as fraud.

However, California law does require a seller to offer a 2-day contract cancellation option on used vehicles with a purchase price of less than $40,000, subject to certain statutory conditions. This contract cancellation option requirement does not apply to the sale of a recreational vehicle, a motorcycle, or an off-highway motor vehicle subject to identification under California law. See the vehicle contract cancellation option agreement for details.”