Rust is a deal-breaker that photos can hide, so be systematic. High-risk areas to check: 1. Underbody and frame rails—surface rust is normal, but flaking or bubbling paint means advanced corrosion 2. Wheel arches and rocker panels—these trap mud and salt 3. Door bottoms and the trunk floor—water collects here; lift the trunk mat and look for dampness or repair welds 4. Around the windshield and sunroof drains—leaks cause hidden rust in the A-pillars Ask the inspector to do a magnet test: filler-repaired areas won't hold a magnet, indicating past accident repairs. A paint thickness gauge reveals resprayed sections—uniform readings around 80-150 microns are normal; spikes over 300 suggest bodywork. Cars from northern China (salted roads in winter) or coastal cities need extra scrutiny on the underbody. If structural members show corrosion, walk away—repairs rarely restore original strength.

Test-drive cars experience much more mechanical wear due to extreme conditions like cold starts and emergency braking compared to regular family cars. We can identify this by tracing whether the first owner was a 4S dealership or the manufacturer. If so, we will reassess its value based on "operational intensity" standards.

Start with the paperwork: the vehicle registration certificate lists every ownership transfer, and the service book plus dealer maintenance records help confirm mileage. For digital verification, ask the seller for a live video walkaround plus a diagnostic scan report showing the ECU-recorded mileage, which is hard to manipulate. For EVs, request a battery state-of-health (SOH) report — it reveals real usage patterns far better than the odometer. Finally, a pre-shipment inspection by a third party should include structural checks (pillars, chassis rails) to rule out accident repairs. Build "no major accident, no flood or fire damage" into your purchase contract with a refund clause if the inspection contradicts it.