Have just discovered that there is a market for used Lego pieces. As I have boxes of the stuff I wondered if anyone had done this and what is the best place to sell it. There seems to be alot on Ebay but not much actually selling. Seriously need the cash for christmas.
I think that some stuff has collection only because it's too heavy to post. If you're looking to sell lego, put it on eBay, do good photos, so parents can see how much there is in total, how much red, wheels etc, and investigate a courier so you will post the lego and should should get some bidders.
I sold two sets of lego separately last November on Ebay. Got a bit more than 50% of what I had paid for it. Firstly, I googled the sets to check I had all the bits (the instructions were long gone), then I took a nice photo of it set up, and listed it. Got cardboard box free from supermarket for packaging, and sent it via Collect+ from corner shop for just under £4.
Going to check out what else I can flog of DS's this year!!