Cemeteries with nonendowed sections opened before July 1, 1987, shall only be required to endow sections opened after July 1, 1987. On the face of any contract, receipt, or deed used for sales of nonendowed interment rights shall be prominently displayed the words "Nonendowment section." All nonendowed sections shall be identified as such by posting of a legible sign containing the following phrase: "Nonendowment section."