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.

As rubber seals age, "slight oil seepage (oil stains but no dripping)" is very common in used cars and is not considered a major fault. Our recommendation is: as long as the oil level does not drop abnormally, just clean and monitor it regularly after arrival, without the need to immediately incur high costs to disassemble and replace the seals.

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.