4S dealership records are directly connected to the manufacturer's database, making the data hard to tamper with and the most reliable, with original parts guaranteed; third-party repair shops usually are not connected, making their data unverifiable. Therefore, we only consider the connected records from 4S dealerships as valid historical documentation.

We use a calibrated high-precision paint thickness gauge to take multiple measurements on at least 13 metal surfaces of the entire vehicle. The original paint thickness of mainstream Chinese models typically ranges from 90μm to 150μm. If any area exceeds 200μm or even reaches over 500μm, we will directly conclude that the area has undergone bodywork and filler repair.

Many connected features are tied to the car's original market. Start with the basics: the infotainment language, navigation maps and voice assistant may only support Chinese, and some systems require a local SIM or account that cannot be transferred to overseas owners. For driver-assistance systems, check whether the model relies on hardware that works without Chinese map data. Lane keeping and adaptive cruise usually work abroad, but map-dependent features like highway pilot may not. Ask the seller to test each key function on video before shipment: boot-up, touchscreen response, app connectivity and over-the-air update status. Also confirm the battery management system and motor controllers have no region locks. Get written confirmation that the features you are paying for are functional in your destination country, and keep that document with the purchase contract.