Within four years after the date of the first sale, a cemetery company or other seller of mausoleums and garden crypts shall be required to start construction or development of that undeveloped ground or section of a mausoleum or garden crypt in which sales, contracts for sales, or agreements for sales are being made. The construction or development of such undeveloped mausoleum section or garden crypt shall be completed within five years after the date of the first such sale. Completed construction shall be deemed performance for purposes of this chapter.