By Jeanne Feldkamp
From your old clothes that are now considered vintage to that rusting treadmill in the garage, every family has some junk and clutter hanging around. You can always have a garage sale or just give your stuff away. But why not sell it online? That way, you can find a good home for your collection of superhero posters and make some cash at the same time.
And as an online seller, you won't be alone. According to a study by the Pew Internet & American Life Project, about 1 in 6 adults -- that's more than 25 million people -- has sold something online. Most post classified ads on sites like craigslist and Yahoo Classifieds or use auction sites like eBay and Auction Fire.
"This is the era of the anytime, anywhere yard sale," says Amanda Lenhart, senior research specialist at the Pew Internet & American Life Project. "The whole wired world is a flea market."
Ready to turn your trash into someone else's treasure? Learn how to sell your stuff online in four simple steps:
1. Pick the right selling spot
There are plenty of sites to sell your items, but just make sure you read the user agreement for the site you pick. Certain sites (especially auction sites) have rules that prevent you from selling items like alcohol, firearms or medical equipment. To get started, check out the following kinds of sites where you can list your second-hand goodies:
2. Register to sell
Posting an ad on a classified site is as easy as writing your ad and submitting contact information (so you can skip to the next step).
But if you decide to sell your stuff via an online auction, you need to set up shop before you can actually post your ad. For instance, to get started on eBay, you need to go to the site and click Register. Enter your name, address, phone number and email address, then choose a user ID and password. To complete your registration, you'll also need to provide a credit card number so eBay can verify your identity. No charges will be made to the card unless you sell something -- then eBay will take its cut.
3. Prep and write your ad
Next, prepare items for sale by cleaning them and repairing any minor problems (like scratches or rips) so you can make a better profit. It helps if you have the original packaging, too. To ignite a bidding war over your goods, McGinnis offers these tips:
4. Decide on payment terms
Finally, you need to include payment and shipping details in your ad. If you sell to a local buyer, the easiest option is to ask for payment in cash (a check could bounce). If you're shipping the item, you can use a service like the popular PayPal, which gives buyers the flexibility of using a credit or debit card to transfer money to you. Paypal is easy and secure to use -- just follow the site's registration steps and read the terms of service.
And remember the golden rule of online selling: Don't ship or hand over the item until you confirm that you've received payment.
Jeanne Feldkamp is a freelance business and technology writer based in San Francisco, Calif.

