Dial *#06# to get the IMEI number. Verify it on IMEI.info or Apple's check coverage page to ensure it isn't blacklisted or stolen.
The iPhone 7 has known aging issues. Test these specific components: If you want to buy a preowned iPhone - Apple Support (PH) how to buy used iphone 7
Before paying, verify these non-negotiable software and security statuses: Dial *#06# to get the IMEI number
If buying in person, ask the seller to "Erase All Content and Settings" in front of you. If it asks for an Apple ID password they don't have, walk away. 2. Hardware Inspection Checklist Test these specific components: If you want to
Ensure the device is not "Locked to Owner". It should show a "Hello" screen or the home screen without an active Apple ID.
Go to Settings > General > About . Look for "Carrier Lock"; it should say "No SIM restrictions" to work with any provider.