California Code, Civil Code - CIV § 798.39

(a) The management may only demand a security deposit on or before initial occupancy and the security deposit may not be in an amount or value in excess of an amount equal to two months' rent that is charged at the inception of the occupancy, in addition to any rent for the first month.  In no event shall additional security deposits be demanded of a homeowner following the initial occupancy.

(b) As to all security deposits collected on or after January 1, 1989, after the homeowner has promptly paid to the management, within five days of the date the amount is due, all of the rent, utilities, and reasonable service charges for any 12-consecutive-month period subsequent to the collection of the security deposit by the management, or upon resale of the mobilehome, whichever occurs earlier, the management shall, upon the receipt of a written request from the homeowner, refund to the homeowner the amount of the security deposit within 30 days following the end of the 12-consecutive-month period of the prompt payment or the date of the resale of the mobilehome.

(c) As to all security deposits collected prior to January 1, 1989, upon the extension or renewal of the rental agreement or lease between the homeowner and the management, and upon the receipt of a written request from the homeowner, if the homeowner has promptly paid to the management, within five days of the date the amount is due, all of the rent, utilities, and reasonable service charges for the 12-consecutive-month period preceding the receipt of the written request, the management shall refund to the homeowner the amount of the security deposit within 60 days.

(d) As to all security deposits collected prior to January 1, 1989, and not disbursed pursuant to subdivision (c), in the event that the mobilehome park is sold or transferred to any other party or entity, the selling park owner shall deposit in escrow an amount equal to all security deposits that the park owner holds.  The seller's escrow instructions shall direct that, upon close of escrow, the security deposits therein that were held by the selling park owner (including the period in escrow) for 12 months or more, shall be disbursed to the persons who paid the deposits to the selling park owner and promptly paid, within five days of the date the amount is due, all rent, utilities, and reasonable service charges for the 12-month period preceding the close of escrow.

(e) Any and all security deposits in escrow that were held by the selling park owner that are not required to be disbursed pursuant to subdivision (b), (c), or (d) shall be disbursed to the successors in interest to the selling or transferring park owner, who shall have the same obligations of the park's management and ownership specified in this section with respect to security deposits.  The disbursal may be made in escrow by a debit against the selling park owner and a credit to the successors in interest to the selling park owner.

(f) The management shall not be required to place any security deposit collected in an interest-bearing account or to provide a homeowner with any interest on the security deposit collected.

(g) Nothing in this section shall affect the validity of title to real property transferred in violation of this section.