China has a large number of luxury cars and a fast turnover rate. For luxury cars of the same year and mileage, the FOB offshore price in the Chinese market usually still has a 10%-15% arbitrage opportunity after deducting shipping costs, especially for models with high depreciation rates.

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.

Testing is mandatory. Troubleshooting electrical devices in the car is part of the standard procedure. We will test the window lift motors, mirror folding, air conditioning compressor and fan, electric seat tracks, etc. Any stuttering or failure of electronic components will be recorded.