HEPCO is an Iranian corporation that manufactures construction equipment and it holds a supply chain with a traditional non-integrated approach. The materials come from four different sources including the engineering and parts company, purchase from domestic vendors, purchase from international vendors, and the company supplies the materials and components needed for assembling of products and delivering to customers. Having a non-integrated supply chain has led to an increase in total cost. Therefore, in order to reduce supply chain cost in this company, a three-level model including...