We use an internationally certified electronic signature platform (such as DocuSign or Adobe Sign). Each signed contract generates a digital certificate with a timestamp and encrypted hash value, which has full legal defense effectiveness in international arbitration courts.

Yes, all external lighting sources, including low beams, high beams, fog lights, daytime running lights, reverse lights, and brake lights, are included in the mandatory power-on testing.

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).