The NEAT duo has found that when most people shop for organizational solutions, they tend to overbuy plastic storage bins, to stow large things they don't use often, and small baskets, thinking they've got a lot of similar little items that need a home. But if they haven't first done a thorough purge, they end up with bins that don't fit their space and with fewer longterm storage needs and less itsy-bitsy clutter than they imagined. Ashley and Molly abide by this bedrock organizing principle: First, make piles of what you have, then shop with measurements-in-hand of the specific places in the home where the stuff will go. And don't forget to buy enough hangers and files; the two other items people underpurchase. They'll come in handy when you need to hang up costumes and put away cards—which the organizers discovered are two of the most commonly hoarded items among men and women respectively.