Abstract- Recently, in Mathematical and Computational Applications Journal Chiu et al. [1] and Chen and Chiu [2] propose an inventory model based on EPQ with rework to determine the replenishment lot size and the number of shipments for a vendor-buyer integrated production-inventory system. They solve the inventory problem by considering both variables as continuous. However, the number of shipments must be considered as discrete variable. In this direction, this paper revisits and solves the inventory problem of [1][2] considering the decision variables according to their nature. Two easy and improved algorithms are proposed which simplify and complement the research works of [1][2].