Depends on what the car looks like that comes with it.

As mentioned above, it's worth whatever you are willing to let it go for...but that's only half of the equation. The other half is, "whatever someone is willing to pay for it." If those 2 things, match up, you have the true value of the car, widget, whatever. If they can never match up, then either the buyer, the seller or both are just daydreaming.