http://finance.yahoo.com/family-home/article/107117/10-Things-Gas-Stations-Won%27t-Tell-Youfollowing are a few paragraphs snipped from the 10 things
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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.
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Stations earn on average between 10 and 15 cents on a gallon of gas. Ironically, they earn the least when prices are highest. When fuel climbs, gas stations must shrink their profit margin to remain competitive, meaning they earn less per gallon than usual. But another big cost during tough times is something they can’t do anything about—credit card fees, which add up to about 2.5 percent of all purchases. When gas is at, say, $2 a gallon, the station pays credit card companies 5 cents a gallon; when gas hits $3, that fee becomes 7.5 cents—more than half the station’s entire average profit. “Those credit card fees are miserable for the gas station business,” says Mohsen Arabshahi, who owns five Southern California gas stations.
How do station owners make up for lost revenue? “Prices go up like a rocket and come down like a feather,” says Richard Gilbert, a professor of economics at UC Berkeley. For several weeks after wholesale prices drop, stations can earn as much as 20 cents a gallon before retail prices are lowered to reflect the change.
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Your debit card might be a convenient way to pay for gas, but it’s a no-win proposition. When you swipe a debit card at the pump, the bank doesn’t know how much money you’ll be spending until you’ve finished pumping. So to make sure you have the funds to cover the purchase, some stations ask banks to automatically set aside some of your money: That amount can be $20 or more. That means even if you just topped off your tank for $10, you could be out $30, $50, even $100 until the station sends over its bulk transactions, which can take up to three days. If your funds are running low, you might end up bouncing a check in the meantime—even though you had the money in your account.
(wow)
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It’s hard to know if you’re getting all the gas you paid for at the pump. But in some places there’s a very good chance you’re not. The state or county weightsand- measures department usually checks pumps for accuracy, but in some areas it can be years between inspections. Arizona, for example, has only 18 staff members to check the state’s 2,300 stations.
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