What to check before buying a used phone

A used handset can be a genuine bargain or an expensive mistake, and the difference usually comes down to three checks you can do while you are standing at the counter.

Start with the IMEI. Dial *#06# and run the number through your network's blacklist checker. A blocked handset is worthless no matter how clean it looks, and no amount of resetting will bring it back.

Then battery health. On iOS it is in Settings under Battery; on Android you will usually need an app, or you can ask us, every phone we list has had its battery capacity measured on the bench and written into the condition report.

Finally, look for the liquid contact indicator, a small white square in the SIM tray that turns pink or red once it has been wet. Water damage often shows up months later as a failing microphone or a camera that will not focus.