My father in law in balt Md does interiors. INdeed, costs run from a little to unlimited, all depends upon what you want!

Sulpted door panels, inserts with logos/flames/patterns, etc, trunk, healdliner, leather vs cloth, etc, etc.

His biz does so well that you have to chase HIM down, and then wait a year to get your car into the shop.

Once in a while i can get a 'christmas gift' from him...the top on my Lincoln, a custom motorcycle seat - little stuff. Getting the leather redone on my lincoln seats, well, he wants paid for that! Oh well!

I will second the 14-20 with your labor, less drivetrain. There are always variables...brakes, wheels, bodystyle, etc.