Retailers often don't let you combine coupons, says Mendelsohn. But you can combine gift cards and coupons and really leverage your buying power, she says.
"You have free money, and you can use a coupon," says Mendelsohn. "So take advantage of it."
Her tip: Go online and search the retailer's site for either coupons or coupon codes. If it doesn't specify "online only," they have to honor it in the store, says Mendelsohn.
And, if you have a smartphone, you can carry the online coupon there, just in case you need to show it to the clerk, she says.