Once you and a buyer are in agreement over the price, you ship the system to the exchange's facility, where their technicians run diagnostic tests. For their involvement, the exchange charges sellers a commission ranging from 10 to 15 percent of the sale price, depending on how much it goes for, says Michael Jordan, the exchange's president. You can also try selling to a used computer dealer, who will buy your PC and keep it in inventory until it finds a buyer. Simply taking your clunker to a store can be less of a hassle than shipping it or haggling with buyers. You'll usually get the best deal by selling your machine yourself.
Newspapers carry classified ads for used-computer equipment.
Another option is to use the Internet. As long as you have Internet access, ads on the Internet are free. Doing business over the Internet is relatively safe, says King. This can be a smart choice if you can't do without a computer. If your new system has to go into the shop for repairs, you'll have a backup.