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.

The lifespan of rubber sealing strips for frameless doors is usually only 4-5 years. We carefully press the sealing strip at the edge of the roof to check for loss of elasticity and use a high-pressure water gun to wash the seams of the windows to check for direct water leakage due to aging.

The registration certificate will show whether the previous owner was an individual (registered with ID) or a company (registered with a business license). Vehicles under a company may be driven by multiple people, so we will focus on checking the uniformity of interior wear and the condition of the chassis.