>"You can't build a "Ferarri shaped car" at the same price as an Chevy Impala because the shape is a part of the cost."

I don't know how it compares to the cost of a Chevy Impala, but it's definitely possible to get the Ferrari look on a budget, here's one example of a kit to convert a Toyota MR2 to look like a Ferrari F360 (similar kits exist for other cars):

http://www.kitcargrp.co.uk/