10 September 2026 · 6 min read

Buying a used phone or laptop: the ten-minute check that avoids regret

Stolen, locked, or a battery on its last legs — the three ways a used device disappoints, and how to test for all of them before you pay.

Electronics are the fastest-moving category on any classifieds site, and the easiest place to lose money quietly. A phone can look flawless and still be blacklisted, iCloud-locked, or running a battery at 71% health. All three are detectable in about ten minutes.

Phones: check ownership before condition

  • Dial *#06# to get the IMEI and check it against your country's blacklist service. A blacklisted handset will not work on local networks.
  • Make sure the seller signs out of their account and performs a factory reset in front of you. A device still tied to an iCloud or Google account is a paperweight.
  • Check battery health in settings (iPhone) or with a battery app (Android). Below about 85% means a replacement soon.
  • Test both cameras, every speaker, the microphone, charging port, fingerprint sensor and face unlock.
  • Insert your own SIM and make a call before paying.

Laptops: the parts that are expensive to fix

  • Boot it from cold and time it. Watch for a BIOS or firmware password prompt — that locks the machine permanently.
  • Check the battery cycle count and health in system information.
  • Look at the screen on a white background for dead pixels, and on black for backlight bleed.
  • Type every key in a text field, test both USB sides, the headphone jack, camera and Wi-Fi.
  • Listen for fan noise under load and feel the base — persistent heat means a thermal problem.
  • Confirm the storage type and size actually match the advert; swapped drives are common.

Accessories and paperwork matter more than you think

The original box with a matching serial number, the receipt and the genuine charger together add real value and, more importantly, suggest the device was legitimately bought. A seller who has none of these and cannot say where the device came from is worth skipping even at a good price.

Meet where you can test properly

You need power, Wi-Fi and light — a mall, a café or a phone shop, never a street corner. Take the full ten minutes. A seller with nothing to hide will wait; a seller who rushes you is telling you something.