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.

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).

We will use a megohmmeter (insulation resistance tester) to measure the insulation resistance of the high-voltage bus. If the resistance value is below the national safety standard, it indicates a risk of leakage, and the vehicle will be deemed unqualified.