So far I have never handled a stolen phone as far as I know so I don't know much about that angle. What I get are peoples old iPhone 7's that have been sitting in a drawer for a few years. They are eager to donate them but have no idea how to get their personal data off them, so the work I do is sitting down with them and walking them through the process. I would say that's about 1 hour per phone including getting to and from the donor, teaching them how to reset their iCloud account password (or Samsung account, whatever) to erase the phone. When I get a carrier locked phone I sell it on eBay and buy an unlocked phone or a bunch of chargers and cables. I'm always happy when the phone is from Verizon or was bought unlocked, but AT&T is better than most.