Once a buyer contacts him via craigslist, he finds out the persons general vicinity, brings the bike to the area and locks it up with a combo lock based chain. He will give you the address of the bike, and if you like it, can make the purchase online and you receive the combination. If you don't want it, he can pick it up who knows when - or leave it for someone else to check out. If the bike gets stolen, he hasn't lost anything on his bottom line and at no point is he in physical communication with the actual purchaser.