Strict definition: All metal body parts (doors, hood, fenders) and the frame must retain the original factory paint, with uniform paint thickness readings. Minor touch-ups or replacements of plastic bumpers, as they do not affect metal corrosion protection and vehicle structure, can still be classified as "original paint" in a broad sense, but we will separately note the condition of the bumper.

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 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.