(a) To the extent that a trustee accounts for receipts from rental property under this section, the trustee shall allocate an amount received as rent of real or personal property to income, including an amount received for cancellation or renewal of a lease.
(b) An amount received as a refundable deposit, including a security deposit or a deposit that is to be applied as rent for future periods, (1) shall be added to principal;
(2) shall be held subject to the terms of the lease; and
(3) is not available for distribution to a beneficiary until the trustee's contractual obligations have been satisfied with respect to that amount.