It takes about five years of driving a hybrid for the savings to catch up to the extra cost of the fuel-efficient car. One quick way to start seeing real savings really fast is to buy a used hybrid. With over 2 million hybrid cars sold in the United States annually, car dealerships are flush with lightly used hybrids that are marked way below their sticker price. Make sure you buy a used hybrid that comes with a warranty; many dealers offer up to 7-year/100,000-mile warranties. But if you see a used hybrid with more than 100,000 miles on it, consider avoiding it, since it can be expensive to replace the battery.