Cal. Pub. Util. Code § 105230

The district shall have power to purchase rail transit equipment such as cars or rolling equipment; and may execute agreements, leases, and equipment trust certificates in the forms customarily used by private corporations engaged in the rail transit business appropriate to effect purchase and leasing of rail transit equipment and may dispose of the equipment trust certificates upon the terms and conditions the board deems appropriate. Payment for the equipment, or rentals therefor, may be made in installments, and the deferred installments may be evidenced by equipment trust certificates payable from any source or sources of funds specified in the certificates that are or will be legally available to the district. Title to the equipment shall not rest in the district until the equipment trust certificates are paid.