It's extremely difficult. The security level of Chinese brand immobilizers is very high, and you must connect a specialized factory computer to the vehicle's OBD and be online with the domestic server to match it. Losing all keys usually means you need to replace the entire lock cylinder and anti-theft control module while overseas.

It depends on the situation. If the video inspection reveals significant mechanical faults or structural damage not disclosed in the inspection report, the deposit will be refunded 100% unconditionally; however, if the buyer defaults for subjective reasons (such as suddenly not liking the color or financial issues), the deposit will be retained as compensation for taking the vehicle off the market.

Once the car system (especially in a closed ecosystem) undergoes a major version upgrade, its bootloader is usually locked, preventing downgrades. If this happens, there is basically no solution in an overseas environment. Therefore, we strongly warn: do not blindly insert a USB drive to upgrade while offline.