Below is an excerpt from the book "1,001 Things They Won't Tell You," which was published in May 2009 and highlights popular columns from SmartMoney's long-running "10 Things" feature.
When it comes to gas prices, most stations are branded—meaning the name of a major oil company hangs out front—and must buy gas from their proprietary company. They can’t shop around. With a lock on sales, the oil companies charge each station a different price depending on various factors, such as the station’s competition and its location. That means a station can pay as much as 46 cents a gallon more than one down the street, and that cost gets passed along to you.
Faced with such instability, Gainesville, Fla., resident Steven King plans ahead: “If I know I’m going out of town, I try not to buy gas so I can fill up after I leave.” King says he can save 10 cents a gallon by purchasing gas on the road. You’d be similarly wise to shop around—with prices constantly in motion, the cheapest gas may not be at the same station every time.