To maximize ROI, calculate the Total Cost of Ownership (TCO), which includes the initial purchase price, software subscription fees, and maintenance costs. Look for suppliers on Made-in-China.com that offer modular designs, allowing you to expand the number of lockers or coils without replacing the entire main unit. Negotiate for bulk discounts (typically 10-20% for 5+ units) and request a comprehensive warranty of at least 2 years on critical electronic components to reduce long-term operational risks.