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).

The registration certificate will show whether the previous owner was an individual (registered with ID) or a company (registered with a business license). Vehicles under a company may be driven by multiple people, so we will focus on checking the uniformity of interior wear and the condition of the chassis.

Currently, in most developing countries, there is a severe lack of deep repair capabilities for the three electric systems. We recommend that B2B car dealers must have basic electrical insulation testing capabilities.