Nearly a quarter of a million people follow coupon queen Kati Kiefer's advice on Facebook.
Still, the founder of TrueCouponing.com gets nickeled and dimed just like the rest of us.
Kiefer catches most of the pricing errors at the drug store. She says shoppers need to carefully check to make sure the sales in the weekly flyer do not require a loyalty card.
Amy McGowen tracks her charges daily, comparing receipts with online accounts.
She finds restaurants among the worst offenders. Aside from being charged for items she did not order, McGowan says she found a server added an additional tip not once but on four occasions.
It's not just where you shop and eat -- overcharges also take place at the auto repair shop.
Kiefer told us her dealer recently tried to charge her for a part that was still under warranty. They caught the error while looking over the bill.
Martin Jacobson describes how he felt after discovering the home improvement store charged him tax on tax exempt items. By Florida law, you can't charge taxes on seeds, groceries and a long list of other items.
It’s just smart money to always scan your receipt before leaving the store, restaurant or auto repair shop.
For more ways to save check out: www.truecouponing.com