Not sure how well it'd do as is but maybe just use it as a portal where people can go to book car rentals in Florida for companies like Hertz and whatnot. Have phonenumbers to offices in the big cities of the state. As alot of people visit FL im sure you'd get a decent amount of traffic.
And to add to it, you could provide links for booking airline tickets and flights and other things.
Sorry it wasn't much of an "appraisal" but I'm sure that'd help get you more money for it that you otherwise would.
Ask yourself who would buy this type of name, and then decide how much it hurts not to have an "s" after "car," and you should have an idea of value. The singular version changes the price tag and meaning of the name a great deal. I don't think you'll get anywhere near $xxxx, but you might get low $xxx.
Thanks for these inputs.
I realize floridacars.com would be better. I thought the singoular version may still be suit rental cars but wouldnt be that good for new cars businesses.