(REAL SIMPLE) -- If you're ready to make a clean sweep of your house, help is here. Experts share the six main reasons why people can't seem to let go of their stuff and their smartest tricks for outwitting that primal hoarding instinct. Prepare to clear out -- for good!

The obstacle: 'If I get rid of this wedding vase, I'll feel guilty'

The solution: People feel a responsibility to be good stewards of things, says Randy Frost, a professor of psychology at Smith College, in Northampton, Massachusetts, and a coauthor of "Buried in Treasures" (Oxford University Press). Especially items they've been given by or inherited from a loved one. Getting rid of a present feels like disrespecting the giver. But remember the true meaning of gifts.

"When you receive a present," says Maxwell Gillingham-Ryan, an interior designer in New York City and the founder of ApartmentTherapy.com, "your duty is to receive it and thank the giver -- not to keep the gift forever."

That goes for items you inherit. "Ask yourself, 'How many things do I really need to honor this person's memory?'" says Frost. Select a few objects with strong associations to your late grandmother, say, and keep them in places where you'll see them. Let the rest go to people who want them more than you do.

Likewise, don't be shy about admitting a mistake you made and moving on. The $120 pair of heels you bought last spring that pinch? Cut yourself some slack and give them away. Real Simple: How to Donate Old Clothes

A look at your love-hate relationship with the possessions that surround you, and how to overcome them

The obstacle: 'But I might need seven sleeping bags one day'

The solution: Everyone fears tossing something out only to realize -- six months, a year, or five years down the road -- that she shouldn't have. Keeping things around "just in case" makes people feel safe.

If your main problem is an overflowing closet, try the "packing for a trip" trick. It goes like this: You're packing for a month's vacation -- you'll need both dressy and casual clothes, for warm and cool weather, and you can fill two big suitcases.

Then take all the other things and place them on a rack in your basement or attic. If you want to wear any of those exiled clothes in the coming days, grab them. But as the months go by, you'll be shocked at how few of those clothes you need or even think about. From there, it's a baby step to a Goodwill bag.

Still have separation anxiety? Box up the stuff you're not quite able to part with and write on the outside, open six months later. Then tuck it away in your basement, attic, or storage facility. If a year from now you find that you didn't miss the items, it will be much easier to part with them.

The obstacle: 'I think this brooch/chair/ugly knickknack might be valuable again'

The solution: When you hear the appraisers on "Antiques Roadshow" say that someone's grandmother's old Bakelite bracelets would now fetch $500, it's easy to wonder whether your vintage piece might be worth a bundle. Stop guessing and find out what the item in question is truly worth.

Take a 10-minute spin on eBay, searching for an item similar to yours. (Click on "Advanced Search," then "Completed Listings Only.") If the sale prices look promising -- or if you can't find equivalent items -- consider having the item appraised by an expert. Many local auction houses will do this for free in the hopes that you will sell the item through them later. (Google "auctions" and your city to find an auction house near you.)

For the greatest certainty, hire an independent appraiser through the American Society of Appraisers or the Appraisers Association of America. Be sure to ask for an estimate first. Real Simple: How to sell old clothes online

Remember -- for something to be considered valuable, it must be in tip-top shape. "People think their old baseball cards or "National Geographics" are worth money," says professional organizer Caitlin Shear. "But that's true only if they're packaged in a Mylar sleeve and in pristine condition."

The obstacle: 'If I put the bills away, I'll never pay them on time'

The solution: Many clutterers have gotten into the habit of organizing their world visually and spatially, says professor Randy Frost. They're afraid that if they put stuff away, they won't remember it, because they won't see it. "But it's a perception of order," he says, "not real order."

You may initially recall that the electric bill is next to the potted plant on the kitchen counter, but it will soon be buried by other items you need to have in plain sight, too, like invitations and permission slips.

Even hard-core clutterers can train themselves to complete tasks without obvious visual cues, says Frost. For starters, if you're used to leaving things in piles, designate a logical home for every object. Set up automatic e-mail reminders to help you remember to pay bills. In addition, if you feel as if out of sight is out of mind, make transparency your friend. Take items destined for closets, the garage, or the basement and store them in clear plastic bins so you can always see what's there. Real Simple: Where to keep important documents

The obstacle: 'I want this chartreuse muumuu to go to a good home'

The solution: People often want to find just the right place for their belongings. The problem is, trying to find just the right place can be paralyzing, says interior designer Maxwell Gillingham-Ryan. And while you wait, say, for your niece to move into a starter apartment, your old love seat and dinette set gather dust.

To satisfy your desire for perfect placement, look for a charity with which you feel a strong connection -- perhaps a shelter for women. To identify a worthy one near you, visit charitynavigator.org, a nonprofit research group that evaluates charities based on how effectively they use donations. Go to the Advanced Search page, select "Human Services" charities, and type in your ZIP code. Contact the three- or four-star charities that interest you and ask if they accept donations.

If that sounds like too much trouble, call your nearest house of worship and inquire whether it has a clothing drive coming up. Ask if the donation is tax-deductible, and get a receipt.

The obstacle: 'I want to declutter, but I can't get motivated'

The solution: This may be due to a phenomenon known as delayed discounting, says Daniel Hommer, M.D., chief of brain imaging at the National Institute on Alcohol Abuse and Alcoholism, in Bethesda, Maryland, and an expert on motivation. It works like this: If it takes a long time to reach a goal, you value that goal less than if you could reach it quickly -- making it harder to get started. Make projects small and rewards immediate, says Hommer.

After you organize a distinct area, dress it up -- add decorative paper to the bottom of a now spartan toiletry drawer, for instance. Keep at it and your home will become not only more orderly but also more beautiful.

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