I'm at Costco so often that I feel ... I usually pay $10 for a 22-ounce bag — about half the price of what I've seen for similar granola in regular grocery stores. If I want even more crunch ...

Discover the 7 grocery items Costco shoppers swear by for unbeatable savings, from rotisserie chicken to vanilla extract.

Costco offers deals on bulk groceries, home essentials and more. But exactly how much can you save? I did the math.