Actually, this car is coated with gold leaf, not gold plate; you can see in the third picture a technician is applying gold leaf.

Relatively speaking, gold leaf is not that expensive. A book of 100 sheets of 3.5″ x 3.5″ 24-carat gold leaf can be purchased for anywhere from $60-100.

In the third picture, the technician has applied approximately 25 squares of gold leaf to the left fender. Assuming it takes 100 leaves to coat the entire fender, and assuming that one fender = approximately 10% of the total surface area of the car, it may cost no more than $1000 to entirely coat a car with gold leaf.

Mind you, that is one DELICATE finish to have on a car!