I would stay away from Mitsubishi products in general because of their reliability, but if you have your heart set on an eclipse, the best way to approximate price is to go to the kelley blue book website (
www.kbb.com) and do a free price lookup.
Cracks in the dashboard can be problematic. They tend to grow. A modern, newish dash shouldn't crack on its own in Florida heat. It is probably either low build quality or abuse.
Ultimately the car is worth what you will pay for it. I would haggle with them and stress those two issues you have with it. If they don't get it to a price you like I would walk away.