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Few people really enjoy wasting their hard-earned money, but many of us do it every day by buying new. We could do our pocketbooks, and the environment, a big favor by opting to be the second owner of some of the stuff we buy.

Obviously, some things are best purchased new; lingerie pops to mind. But lots of other stuff depreciates quickly while still having plenty of useable life left. Here are 10 items where the cost vs. use equation strongly tilts toward buying used.

Books, books, books

Now this is awkward, because I wrote a book. (Warning! Shameless plug ahead!) It's called "Your Credit Score: How to Fix, Improve and Protect the 3-Digit Number that Shapes Your Financial Future," and of course, I'd love for you to go out and purchase a new copy. (End of shameless plug.)

But the reality is that most books don't get read more than once, if that, and they're astonishingly easy to find used at steep discounts -- if not absolutely free.

Your local library, for example, may allow you to reserve titles online and then deliver them to your nearest branch for pick-up. Used book stores abound, both in your town and online. If you're looking for a potboiler to get you through your next cross-country flight, just stop by almost any yard sale and pick up four for $1.

Exception: Reference books you'll use again and again. For example, I bought a deeply discounted copy of Cheryl Mendelson's excellent "Home Comforts." That was after checking out the book at the library and running up a small fortune in fines because I couldn't bear to part with it.

Liz Weston

Liz Weston

DVDs and CDs

Some online retailers, like Amazon.com, now surface used versions of many of the DVD movies they sell new. You can find similar deals for online CDs (yes, Virginia, some of us dinosaurs still buy CDs). Other good hunting grounds for purchase of used items: movie rental chains, used record stores and yard sales.

Exception: When you simply must have the latest release by your favorite singer/director/actor, right now. It can take a few days or weeks for the used versions to show up, and perhaps a few months for the price to get discounted enough to compensate for the greater hassle you might face trying to return a defective or unsatisfactory purchase.

Little kids' toys

Parents know: it's all but impossible to predict which toy will be a hit and which will lie forlorn at the bottom of the toy box. So rather than gamble at full price, cruise consignment shops and yard sales for bargains.

Better than cheap, though, is free. Some parents set up regular toy-swapping meets, or you might be lucky enough to score hand-me-downs from friends and relatives.

Exception: Some parents get away with giving used toys for birthdays and holidays, but most of us (and our kids) have been fairly well brainwashed into believing that gifts should be purchased new. Try to opt, though, for classics, like sturdy wooden toys.

Jewelry

Fat markups on most gems (100% or more is fairly common) means that you'd be lucky to get one-third of what you paid at a retail store, should you ever need to sell.

So let somebody else get socked with that depreciation. Find a pawn shop that's been in business for a while, get to know the owner and ask him or her for recommendations. Some readers have had good results buying via newspaper ads and Craigslist, but I'd want to take the piece to a jeweler for an appraisal first.

Exception: You want something custom-made. Even then, consider buying used stones and getting them reset.

Sports equipment

We may buy everything from badminton rackets to weight sets fully intending to wear them out, but too often they wind up collecting dust. Buy someone else's good intention and you'll save some bucks.

Happy hunting grounds: yard sales, newspaper and online ads, resale stores like Play It Again Sports.

Exception: Shoes, baseball mitts and anything else that molds to the wearer's body. In addition, some people shun buying anything used if it has a motor, like a treadmill. They worry they won't get enough use out of the piece before it dies. Given how little work most such devices see before they're sold, though, you might want to take the chance.

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Timeshares

You could call these a notoriously lousy investment if you could call them an investment at all, but you can't -- because what real investment is guaranteed to lose 30% to 70% right off the bat?

That is, unless you buy used. There is always a huge number of folks who caved in to three hours of hard sell and are now desperate to dump their shares.

Exception: Some of the higher-end properties in exclusive resorts don't lose much value, and may offer benefits like frequent-flyer miles that could be worth the extra money if you buy from the developer. Before you buy, though, check resale values online; don't take an agent's word for how much depreciation to expect. Also, a relatively new type of expensive time share, called a fractional interest, may actually gain in value over time.