(a) A seller may not include as a term of the executory contract a provision that:
(1) imposes an additional late-payment fee that exceeds the lesser of:
(A) eight percent of the monthly payment under the contract; or
(B) the actual administrative cost of processing the late payment;
(2) prohibits the purchaser from pledging the purchaser's interest in the property as security to obtain a loan to place improvements, including utility improvements or fire protection improvements, on the property;
(3) imposes a prepayment penalty or any similar fee if the purchaser elects to pay the entire amount due under the contract before the scheduled payment date under the contract;
(4) forfeits an option fee or other option payment paid under the contract for a late payment; or
(5) increases the purchase price, imposes a fee or charge of any type, or otherwise penalizes a purchaser leasing property with an option to buy the property for requesting repairs or exercising any other right under Chapter 92.
(b) A provision of the executory contract that purports to waive a right or exempt a party from a liability or duty under this subchapter is void.