California Code, Civil Code - CIV § 1812.625

(a) The lessor may require the consumer to pay a security deposit, however denominated, in an amount not to exceed the equivalent of one month's rental only for the purpose of satisfying any lawful claim by the lessor, up to the maximum described in subdivision (a) of Section 1812.627, for those amounts reasonably necessary to pay for the loss of the property or the repair of damage, exclusive of reasonable wear and tear.

(b) Within two weeks after the lessor has taken possession of the property from the consumer, the lessor shall deliver to the consumer the amount of the security deposit less the amount, if any, deducted for loss or repair as permitted by this title. If any amount is deducted, the lessor shall also deliver to the consumer at that time a copy of an itemized statement indicating the amount of the security deposit, the amount deducted for loss or repair, and a detailed statement of the basis for the deduction. Delivery may be made by personal delivery or by first-class mail, postage prepaid.