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 do not rely on the seller's verbal assurances. We provide multi-dimensional accident-free certification by cross-referencing insurance claims records, service orders from authorized dealerships, and conducting on-site paint thickness measurements and weld point inspections of the chassis and structural components (longitudinal beams, A/B/C pillars, shock absorber mounts).

We use two steps: 1. Insert a medical-grade endoscope through the spark plug hole to visually inspect cylinder wall scratches and carbon buildup on the piston top; 2. Extract an engine oil sample to check for large metal debris or emulsification (caused by coolant leakage).