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 car owners do not have their first maintenance done at authorized dealerships, leading to gaps in early data. In such cases, we do not blindly trust the odometer; instead, we analyze the tire production dates and wear levels, as well as the depth of grooves on the brake disc edges, using the "gold standard" of physical wear to infer the intensity of early use.

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.