DnD Miniatures in bulk?

Hey guys, I'm looking to get more DnD miniatures and am constantly on the lookout to buy them in sets or bulk. I constantly stop at places like Misfit Toys, Nan's, Third Planet, Gerard's and a lot of other places that sell them individually, however I am looking to buy them more in bulk used. Does anyone know someone who is selling some of their old minis or any other store who sells them by the bulk or set? Thanks in advance.