When sourcing low-cost sneakers, focus on the Upper Material and Outsole Composition. For the upper, PU (Polyurethane) leather or synthetic mesh are cost-effective alternatives to genuine leather. Ensure the PU is breathable and has a thickness of at least 1.2mm to prevent cracking. For the outsole, PVC is the most economical, but TPR (Thermoplastic Rubber) offers better flexibility and slip resistance at a slightly higher price point. Always request a material safety data sheet (MSDS) to ensure the glues used are non-toxic.