If you want to get a reliable iPhone that you know is not stolen, get a certified refurbished phone from a reputable company like Backmarket.com or go directly to Apple. This way you get a phone that you know is useable and it comes with a warranty. Don’t mess around with sketchy idiots, that’s a sure way to get ripped off. If you know the person thats one thing, but some random from the internet? Not in a million years would I trust them. I got my 13 pro max from Backmarket and I am happy. Good Luck