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).

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).

It usually refers to very small stone chips on the hood from high-speed driving, nail scratches on the inside of door handles, slight curb scratches on the edges of wheels, and minor wear on interior plastic parts. These do not affect the vehicle's functionality or corrosion resistance.