Cal. Civ. Code § 70-24-201

(1) A landlord and a tenant may include in a rental agreement terms and conditions not prohibited by this chapter or other rule or law, including rent, term of the agreement, and other provisions governing the rights and obligations of the parties.
(2) Unless the rental agreement provides otherwise:
(a) the tenant shall pay as rent the rental value for the use and occupancy of the dwelling unit as determined by the landlord;
(b) rent is payable at the landlord's address or using electronic funds transfer to an account designated for the payment of rent by the landlord;
(c) periodic rent is payable at the beginning of a term of a month or less and otherwise in equal monthly installments at the beginning of each month;
(d) rent is uniformly apportionable from day to day;
(e) the tenancy is week to week in the case of a roomer who pays weekly rent and in all other cases month to month; and
(f) if either party terminates the rental agreement without cause prior to the expiration date of the lease term, the aggrieved party is entitled to monetary damages up to 1 month's rent or an amount that is agreed on in the rental agreement, which may not exceed 1 month's rent. Landlords shall follow 70-24-426 (3) and are entitled to rent from defaulting tenants up to the date a new tenancy starts or the date the rental agreement term expires.
(3) Rent is payable without demand or notice at the time and place agreed upon by the parties or provided for by subsection (2).
(4) A landlord may not charge an additional fee based on rent payment type except to recoup an electronic bank fee incurred for electronic payment.