The stuff in your attic or basement could land you a jackpot. By Pat Mertz Esswein, Associate Editor From Kiplinger's Personal Finance, August 2013. Updated April 2014 1. What’s hot. Mid 20th century Modern furniture and decorative items are hugely popular, says Atlanta appraiser Valerie Hale. Funky art, costume jewelry and purses from the 1950s through the 1970s are also in vogue, as are regional pottery and glass. The rarer the item, the more pristine its condition (original packaging is a plus) and the better your documentation (the item’s history, including your proof of ownership), the more money it will bring. Hale says there is little demand for items such as small Hummel figurines, which sold 20 years ago for $150 apiece and now sell for $25 on eBay. SEE ALSO: Quiz -- How Much Is Your Junk Worth? 2. Get a ballpark price. Look for comparable items that have sold recently on eBay or LiveAuctioneers.com (see the “auction results database”). Or subscribe to a database of auction-house sales, such as Invaluable ($45 per month) or Prices4Antiques.com ($29.95 for 15 days; $52 for 30 days). Both offer free previews (or you can access them at your public library). Use them, too, to identify auction houses that specialize in your type of item. Collectors and hobbyists can also help you value and sell your stuff. For example, amateur radio clubs often help the families of a “silent key” (a deceased member) find buyers for radios and related gear. 3. Of Barbies and baseball cards. Barbie dolls from the ’60s will sell if they’re undamaged and in their original boxes, says Josh Tane, of estate seller Adams Unlimited, in Mount Vernon, N.Y. Collectors are also buying very fine, old German and French dolls in porcelain and bisque. High-value sports cards are those printed in 1969 or earlier, according to Heritage Auctions, in Dallas. The ultimate collection? Cousins Karl Kissner and Karla Hench of Defiance, Ohio, found a cache of nearly mint-condition baseball cards dating from 1910 while cleaning out their aunt’s attic. Heritage estimated their value at $2 million. 4. Hire an appraiser. An appraiser who specializes in personal property and your type of collection can give you an expert written opinion and help you identify other objects of potential value. Look for one accredited by the Appraisers Association of America, the American Society of Appraisers or the International Society of Appraisers. Appraisers typically charge $75 to $150 an hour. Advertisement 5. Let a pro sell it for you. A local antiques dealer or estate-sale company will buy most of your stuff for about 30% to 50% of what the company estimates it will go for. An auction house will advertise to interested buyers and take a fee equal to 20% to 30% of the final sale price. Consignment shops price and sell vintage accessories and typically take 45% to 50% of the final price. Note: Such middlemen can be selective. 6. Or do it yourself. You can conduct an online auction at eBay (list your first 50 items per month free; eBay takes 10% of the total sale amount, up to a maximum of $250 per item). Start the bidding low, and don’t hold out for a reserve, or minimum, price that buyers must meet, advises Tane. You can sell vintage goods that are at least 20 years old on Etsy.com (20 cents to list an item for four months, plus 3.5% of the sale price). But Etsy isn’t an auction site, so your price won’t be bid up. You’ll make out best if items are sold individually or in small lots.