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.

We will use a megohmmeter (insulation resistance tester) to measure the insulation resistance of the high-voltage bus. If the resistance value is below the national safety standard, it indicates a risk of leakage, and the vehicle will be deemed unqualified.

We will check if the vehicle identification number (VIN) is within the official recall batch. If there are any outstanding safety recalls (such as replacing Takata airbags), we will require the original owner to assist in sending it to an official 4S shop to complete the free recall work before the vehicle is deregistered.