What should you check when buying a second-hand phone?

With a second-hand phone, the biggest risk isn't the price but an unregistered device. Phones brought in from abroad without being registered stop working with lines in Türkiye after a while; you're left with a device you can't use.

The second risk is the device staying locked to the previous owner's account. A phone that hasn't been signed out of its Google or Apple account won't open even if it's reset. The order below eliminates both of these risks.

1. Get the IMEI number Type *#06# on the phone's keypad. The IMEI number appears on the screen (two of them if it's dual-SIM). Check that the number on the box and in the settings menu is the same too. 💡 If the IMEI on the box and the one on the phone differ, the device may have been swapped; don't buy it.
2. Check the IMEI on e-Devlet Open the “IMEI Query” service on turkiye.gov.tr and query the number. It should show as “Registered”. If it turns out to be unregistered, the device won't be able to connect to the network after a while. 💡 Do the query while you're with the seller, from your own device.
3. Confirm the device isn't locked In the settings, see that the device has been reset to factory settings and signed out of the previous account. The Google account on Android, and “Find My iPhone” on iPhone, must be off. 💡 If the seller says “I'll sign out later”, don't buy it; it can be locked remotely.
4. Test the screen and the touchscreen Open an image with a white background and one with a black background; look for dead pixels, blotches and color differences. Try the touchscreen by tapping every corner of the screen.
5. Look at the battery health On iPhone: Settings → Battery → Battery Health; on Android: the manufacturer's app or the battery information screen. A battery below 80% will need replacing before long. 💡 You can use the cost of a battery replacement as a bargaining chip.
6. Try the camera, speaker and charging port Take a photo with the front and rear cameras, record audio, play it through the speaker, plug in a charging cable and see that it charges.
7. Ask for an invoice and a handover record If possible, get the invoice. If not, have the seller sign a simple handover note stating their name, contact details and the device's IMEI. 💡 If you're buying it by shipping, choose a method that lets you pay after you've received it.

⚠ This guide is general information. Yudum cannot be held responsible for the outcome of following it; for official procedures always rely on the institution's own statement. Steps and fees change over time.

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