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).

If the buyer's country is under international sanctions, or if the buyer fails to provide a legitimate source of funds leading to the bank returning the payment, all transfer fees and exchange rate losses incurred during this period are to be borne entirely by the buyer.

Changes must be requested before the shipping cut-off date (SI Cut-off Date) prior to the vessel's departure. Once the vessel has sailed, the shipping company will charge a high amendment fee, which may also cause delays in customs clearance at the destination port, with costs borne by the buyer.