NEW YORK (CBSNewYork) -- Savvy shoppers are using a powerful tool to save money, and all it takes is some homework and a simple question.
As CBS 2's Kristine Johnson reported Monday, the tool is called price matching, in which stores let consumers pay the lowest advertised price without trekking from store to store.
"Just this week I bought a toy, saved three bucks -- bought my coffee that day," said Maria Smith, a busy mother of four.
But the process is not quite as simple as it seems. Undercover cameras have put price matching to the test.
Shopping undercover revealed what happened on the price-matching front lines. One major chain sold an electric screwdriver for $99, but a scan of the bar code showed an online retailer was offering it for $94.99.
But a price matching request at checkout produced only confusion. The clerk and the supervisor did not know what to do.
"There are times when the store employee is not going to know their own policy," Smith said.
It turned out the store's policy did not allow price matching of online retailers. The customer service desk matched the price, taking off $5.
"Some employees will stick exactly to the script as corporate policy writes when it comes to price matching," said Louis DeNicola of Cheapism.com. "Others will go out of their way to help shoppers."
But Cheapism.com, a deal website, warned that stores sometimes play sales hardball.
"Although you might see a television that's 42 inches, it has the exact same specifications between two different stores, you'll find out that store A has a very specific model number because they've moved the power button to the left side. You won't be able to price match it in store B," DeNicola said.
Price matching for a computer monitor did not work in one store. The clerk pulled up a list of retailers approved for price matching, and said the better deal was not on the list.
Experts said the marketplace is constantly changing.
"Retailers must be able to react in the moment to a particular customer situation, and on the fly figure out how to become competitive with either somebody next door or somebody around the world," said consultant Allen Adamson.
Smith said if she cannot get the deal, she looks for the exit.
"If the store doesn't match the other retailers' price, there are times when I have walked out and not bought the item," she said.
Some stores will also match prices a week after a customer buys an item, if they find a lower price at another store. Just bringing in an original receipt and proof of the competition's price is sufficient.
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