1. Good people—Buy from a trusted seller. "Check the percentage of positive feedback, read the feedback messages, and most importantly look through the sellers' items up for auction and focus on those known for selling designer items."
2. Good quality—Look for key authenticity points. "Most trusted sellers on eBay will show detailed images of each item, including holograms, date codes, stitching, and any other details key for authenticity. If detail shots aren't available, request them from the seller. If you don't know the key authenticity points, look into authenticity guides like this one from eDrop-Off."