Rust is one of the most underestimated problems in remote buying. Request specific evidence: photos of the underbody, wheel arches, door sills, and around the windshield seal; close-ups of suspension mounting points; and ideally paint thickness readings across panels (factory paint is typically 80-120μm; heavy patches suggest bodywork). Northern Chinese cars may have winter road-salt corrosion; coastal cars can show surface rust on exposed metal. Surface rust on exhaust and bolts is normal—structural rust on frame rails, subframes, or brake lines is a deal-breaker, especially if the car is headed to a humid or coastal market. Have the inspector tap suspicious areas during the video call: flaky or bubbling metal sounds hollow. Walk away if the seller refuses underbody photos.

For older vehicles or those used in high temperature and humidity areas, we will focus on opening the hood to check if the insulation of the wiring harness in the high-temperature area of the engine compartment is cracked or brittle, to identify potential short circuit risks that could lead to spontaneous combustion.

Interior assessment is divided into three core areas: the driver's high-frequency contact area (steering wheel, gear shift, edge of the driver's seat), central control button area, and rear seats and ceiling. The natural sheen of leather surfaces (patina) is normal; however, any physical damage (such as leather tearing, fabric burn holes, or plastic breakage) will be classified as "structural interior damage" and clearly marked.