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.

From a technical perspective, China's "National VI B (China VI-b)" is one of the strictest emission standards globally, with limits on carbon monoxide, nitrogen oxides, and particulate matter that are even stricter than some of Europe's Euro VI standards. However, the two are not legally recognized by each other, depending on your country's import regulations.

Odometer tampering is a common risk in the global used car industry. We verify the data by extracting transmission mileage from the OBD computer, checking the most recent maintenance record's mileage, and consulting the national traffic management app for annual inspection records. If there are irreconcilable discrepancies or conflicts in the data, we classify it as a tampered vehicle and refuse to export it.