We used to go to a LOT of estate sales, getting there at 4 AM to get on "the list," then waiting in the car for it to start. Kind of a big adventure. I've gotten 2 Singer Featherweights that way, for reasonable prices. You need to be one of the first group to go in otherwise the good stuff gets grabbed up or saved right away. I've only found actual quilting fabric or books a few times...really great prices though. There are many nice things at sales but it's sure easy to become a hoarder!
I have seen so many unfinished projects, or quilts that no one in the family must've wanted. I've snatched up quite a few. It's kind of sad. My daughter said she'd take my stuff, but since she doesn't quilt, I suppose she could just be saying that. I'll tell her about a local guild. Whoever gets my stuff will probably be very pleased! I used to fret about it and think I needed to use it up as fast as I could, but it's not going to happen. So whatever happens, happens.
Recently on the internet I saw 68 boxes of someone's fabric at a quilt shop for $1200. I would hope mine would fetch more than that!