So you're implying a clean car won't sell for more money than a dirty car? Thats on the buyer to decide but we all already know that people will pay more for a cleaner car. The coin comment about grading is also missing the point; that a judgement on an items current condition is exactly "grading". We generally go by used, SU, or new but that is grading. There are also subgrades between those grades. Wether it is done by third party or not doesnt matter.