Step away, step away, step away.
Costco Exterior
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You know ye olde Costco drill. Check everything off your shopping list. Add a few extra jars of peanut butter for good measure. Is that patio furniture on sale? Don't mind if we do.

While Costco can be great retailer for deep savings, it can also be a landmine for impulse shopping. As Costco warehouse designer Stan Laegreid described in Fast Company, there's a specific area that can trigger overspending: The front of the store. As he wrote in the wonderfully-titled article, "The Choreography Of Design, Treasure Hunts, And Hot Dogs That Have Made Costco So Successful," this is where Costco puts "luxe" offerings like televisions, computers, and electronics. In addition to these flashy buys, there are also some other alluring treasures; "[a]dd the unexpected but exotic offerings: a Cartier watch or a Prada handbag, or, on at least one occasion, an original Picasso. They may be for sale at a much reduced price, but likely for only a fleeting moment," advises Laegreid.

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Of course, that designer handbag may seem like quite the deal, but if you only came to pick up Kirkland Signature EVOO and some party snacks, and walk out with a Prada handbag, you don't need us to say your credit card bill may make your eyes pop.