LOL
Sorry you're looking at Craigslist for info on Cars?
I'm sorry but that's the biggest mistake you can make. People lie constantly on Craigslist so they can sell Cars.
If you want the most Fuel Efficient Car you want the Prius.
http://www.toyota.com/matrix/trims-prices.html
The most standard Matrix gets the best MPG. The S and XRS get worse MPG.
The 2010's aren't out yet either. So I would be VERY wary of what you read on Craigslist.