what are thing to consider while buying used iPhones?

1.Its better to check that tagline" designed in California，assembled in China”is their at bottom of back and other various details along with this

2.Do configure fingerprint settings and see whether it doesn't lags and works fine.

3.Do take instant photos with camera and record video. Do observe no disturbance or lag comes while taking photos and phone takes quick snaps.

4.Original battery.

5. Download CPU Z in phone and compare every specs stated in app with specs from some outer source to check phone authenticity.

6. No scratches on camera glass.

7.Do take instant photos with camera and record video. Do observe no disturbance or lag comes while taking photos and phone takes quick snaps.

8.See if screen is not much damaged or having scratches. Few like 1–4 are considerable but whole screen with tons is not.

9.Check all ports whether headphone jack and charger are not tampered and shows visible hardware damage. And also various buttons like volume, power off, fingerprint button etc.

10.It doesn't heat up much after minutes of usage.

read：What's the best way to extend battery life on my Android phone？