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).

This involves personal privacy, and we have no right or ability to retrieve personal driving violation records from the traffic police system. We can only infer if there was aggressive driving by checking if the engine has been reprogrammed with a higher-level ECU (stage 1/2) or if the transmission has a history of severe overheating.

Completely different. The assessment of commercial vehicles focuses on: the extent of wear/deformation in the cargo area, whether the frame has been twisted due to overload, the fatigue of the leaf springs, and the emissions of the diesel engine. Minor exterior scratches carry very little weight in the assessment of commercial vehicles.