I agree. Someone pointed out that this is a good way to see the pricing history on our cars, and that is a very valid point. So, I retract my suggestion to delete for sale posts.
But I WOULD like to see the posts inverted, so the newest posts are always at the top. If this was used in a "For Sale" thread, then it would be much easier to see cars that are for sale currently, while keeping access to past sales information freely available.