Regarding eBay, first set up an account with them (it's free). Search for your brand and model of machine and, when the search ends, scan along the lefthand side of the screen to find "completed listings" and check that box. It will change the search to list only those that have previously been listed. You need to be logged into your account in order to see that "completed listings" box! When you look at completed listings, be aware that only the green prices are machines that actually sold. Anything with a black listing price was offered for sale but did not actually sell. Your best gauge of price is on machines that actually sold, although sometimes you can add a little to the price when selling locally (because people don't have to deal with the uncertainties of mail and whether the machine actually works or not).