The December holidays are approaching and that means so too are Black Friday sales and Cyber Monday specials. But do sales like these truly offer the discounts they suggest?

Experts say that just the idea that you’re getting a bargain can affect a center of your brain that can cloud your reasoning and make you open your wallet.

“Of course, retailers know this and play on it, by offering deals that really might not be such good bargains,” said Margot Gilman, Consumer Reports money editor.

So how do shoppers know when they’re getting a real steal?

“Go in with your eyes wide open and with a healthy sense of skepticism and take advantage of tools that exist, many apps, that will help you track prices, so you know when a deal is really a bargain,” suggested Gilman.

Before you buy, browser extensions such as The Camelizer, Invisible-Hand or PriceBlink scour the web for the best deals.

Then price alerts, such as CamelCamelCamel, Price-Tracker, Shop it to Me and Slick-Deals, tell you when prices for those items have dropped.

And price comparison apps like Buy-Via, Scan-Life and ShopSavvy can tell you if there’s a better deal out there, online or even at a local store.

If you want price protection even after you’ve shopped, price adjustment apps continue to search the web after you charge something and initiate a refund if prices drop on something you’ve already bought. But you may have to expose your bank and credit card information for some of those apps to work.