A professional pre-purchase inspection in China normally covers five parts: exterior and interior condition, a lift inspection of the chassis and frame, engine bay checks, a road test, and OBD diagnostics. Prioritize the chassis rails and A/B/C pillars for cut-and-weld repairs, engine oil leaks and timing noises, transmission shift quality, and OBD fault codes — cleared codes leave telltale history data. For EVs, add battery pack casing, insulation values, and battery state of health (SOH). Insist on original timestamped photos with the VIN visible and a written conclusion such as 'fit for export' or 'major defects found.' A report that only says 'good condition' is not worth paying for.

Odometer fraud exists everywhere, but cross-checking several data points makes it hard to fake: 1) Maintenance records: ask for service history with mileage entries. Gaps or resets are red flags. 2) Tire wear: a car showing 30,000 km should not have nearly bald tires. Compare tread depth against the claimed mileage. 3) Pedals, steering wheel, and seat bolsters: heavy wear on these with low odometer readings is a classic mismatch. 4) Diagnostic scan: request an OBD readout. Many control modules store mileage data internally — if the ECU shows 120,000 km while the dash shows 40,000, you have your answer. 5) Vehicle history report: in China, apps and platforms can pull insurance claim records and registration history, which often reveal the true mileage trail. Always request a live video showing the odometer with the engine running, and have the number written into your contract.

For gasoline cars, insist on a compression test: each cylinder should read within 10-15% of the others, and the actual values should match factory specs for that engine. A single low cylinder points to worn rings or valve problems that idle checks will never reveal. A leak-down test goes further. It pressurizes each cylinder and measures how much air escapes and where. Air hissing from the oil filler cap means ring wear; from the intake or exhaust means valve issues; bubbles in the radiator coolant mean a head gasket problem. This is the single most revealing test for engine condition. Also request OBD scan data with freeze-frame records, a coolant system pressure test (to catch hidden leaks), and an inspection of the timing belt or chain condition with service history. For electric vehicles, compression tests don't apply — instead ask for a battery health report from the BMS, motor insulation readings, and a road test logging any inverter or drive-unit fault codes. A written report with photos or video of each test is essential evidence for your records.