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).

For B2B large customer orders, a "sampling + full inspection" dual regulation is adopted. Core parameters (no major accidents, no water damage or fire) are subject to 100% inspection per vehicle; appearance and condition are uniformly graded (e.g., uniformly purchasing Grade A), and panoramic images of all vehicles in the batch along with a core indicators comparison list are provided before shipment.

Before export, we perform a standard external wash and interior vacuuming to meet basic hygiene inspection requirements by customs. However, we do not engage in deceptive "refurbishments" (such as repainting large areas with cheap paint or using low-quality interior refurbishing agents) to preserve the vehicle's true physical condition for buyer assessment.