MPG: 30/40; Base Price $19,445. This rating is for the specially equipped LE Eco version of the Toyota Corolla that comes with a modified version of the car’s 1.8-liter four-cylinder engine and assorted tweaks; it starts at $20,280. That’s a few mpg more than the rest of the line can deliver (28/35 mpg with a manual transmission), but you’ll need to own the car for at least 5.5 years to recover the added up-front cost in fuel savings ($150 a year) at today’s gas prices.