Is the late payment penalty in a real estate installment purchase contract, which the buyer can avoid signing and merely initial, considered a deception?

Stipulating a financial penalty on the buyer for delaying the payment of installments due is a forbidden and void usurious condition. It is not permissible to accept it or fulfill it, whether it was a pre-condition or not. As for not signing and merely writing initials to indicate rejection, this matter should be referred to specialists to determine whether it constitutes acceptance or not.