it's just that my desire to get the stance correct on cars causes me to mess with my models - sometimes permanently modifying them - and I know that for most people such modifications reduce the cars value.

I'm a bit strange in that I consider my collection to be a 'dead loss' - just as if I were spending the money on greens fees or going to the opera - its money spent for my enjoyment that I do not expect to get back. It makes me a bit circumspect when giving advice because I know many see investment value in their collections.