I sell my wife's and my old iPhones and Android every couple of years and what I do is take pictures of the serial number and send it to the buyer after they ha

I sell my wife's and my old iPhones and Android every couple of years and what I do is take pictures of the serial number and send it to the buyer after they have paid for the device. Sends a message that I have documentation on what the device is and I can report it stolen if they try pull a scam on me. It also helps the buyer because they can check to see if the phone is reported stolen before even taking possession of the device.