Hey OP, as a grizzled hiker who’s thrifted my way through a decade of trails, I’d skip the hype around “premium” resale sites and hit up local spots like mountain shop consignment stores or even Facebook Marketplace for real deals-often 50-70% off new prices. Online, Patagonia’s Worn Wear program is solid for eco-vibes, but inspect everything: tug zippers for smooth action, feel seams for fraying, and test waterproofing by splashing water on fabric (it should bead up if DWR’s intact). Avoid anything with delaminated Gore-Tex; it’s a money pit. What’s your size range? Might have leads.