Buying a used drone requires more than just a visual check. Ensure you verify the following to avoid a "lemon":

“I've actually used this function for ferrying small objects... The flight control is decent, but not spectacular. The drone does not fly as fast as it claims... the camera is not particularly good (especially in low light).” Reddit · r/drones · 1 year ago

Check the cycle count in the DJI Go 4 app. Batteries with over 150–200 cycles are nearing end-of-life. Inspect for any "puffiness" or swelling, which is a fire risk.

Originally rated for 27–30 minutes , though used batteries may realistically offer 20–22 minutes depending on their health.