Don't do it...they're a quantum leap backward in mileage from a 14 year old Ford Aspire or Ford Escort or any kind of Geo from a decade and a half ago...all those models listed average about 35mpg with the air conditioner running. Get a used one and what you may have to shell out in easy to replace parts you'll save at the pump, for sure.
You have to believe there's something going on between the car companies and oil companies when they're marketing 28mpg as the best we can do, and those hideous, unsafe, and above all *expensive* smart cars get the same (or less) mileage that a regular compact car with a backseat got in 1992.
Oh yeah...I got gas yesterday for my 99 Dodge Ram (full size, 21mpg{?!?!}) and I paid about 3.95 or so. $35 for a quarter tank.