18k or less and buy it on the spot... Ok, will you take a Pure, no options, basic colors? You realize that's a $6k markup or 50%. Careful how you phrase things and how excited you are. The smart is a great car, but if you get so anxious to take anything, you perpetuate the dealer's profiteering.
Nav options, bluetooth, special paint... an orphan? No, that sounds like a dealer profit car there. Nav, bluetooth... a grand. A Cabrio with Nav, full sound system, etc. should run under $22k (am I right, anyone?). $25k sounds like they were selling you every option that got them the most profit. You had every right to turn that down and wait for another one, or even go elsewhere. There's no reason you have to shop at a particular dealer; you can deal with anyone if you're willing to drive there. Check the few dealers north of you, I think there's one in Clearwater. Miami is too expensive anyway, for anything really.