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).

As rubber seals age, "slight oil seepage (oil stains but no dripping)" is very common in used cars and is not considered a major fault. Our recommendation is: as long as the oil level does not drop abnormally, just clean and monitor it regularly after arrival, without the need to immediately incur high costs to disassemble and replace the seals.

It depends on the situation. If the video inspection reveals significant mechanical faults or structural damage not disclosed in the inspection report, the deposit will be refunded 100% unconditionally; however, if the buyer defaults for subjective reasons (such as suddenly not liking the color or financial issues), the deposit will be retained as compensation for taking the vehicle off the market.