Strict definition: All metal body parts (doors, hood, fenders) and the frame must retain the original factory paint, with uniform paint thickness readings. Minor touch-ups or replacements of plastic bumpers, as they do not affect metal corrosion protection and vehicle structure, can still be classified as "original paint" in a broad sense, but we will separately note the condition of the bumper.

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.

Experience turbo lag and power surge during road tests; check for significant oil accumulation at the turbo intake and intercooler connections (slight oil vapor is normal); and use OBD to read the real-time boost pressure peak to see if it meets factory settings.