Checklist before buying a new phone

• Box sealed, with the same IMEI on the box and the phone (dial *#06#).
• PTA status checked by IMEI.
• Screen: no dead pixels, touch works across the whole display.
• Cameras, speakers, microphone and charging port tested.
• Warranty card or receipt with date and shop name.
• Original charger and cable in the box.

Buy from a shop that gives a written warranty and has a fixed address.