[Nick Zwar]

Yes, I can see that… flea markets, garage sales, etc. are probably your best bet to find a bargain. Lukas of course is currently selling of lots of used film scores for good prices (as far as I can see… I haven’t bought anything there… because I bought most of the stuff I wanted back when it came out… few CDs nowadays that I missed), but of course these are still regular “collector’s prices”, not “garage sale prices” from people who don’t know what they’ve got.
I lucked out recently and found the “missing pieces” in my Ligeti collection… I did have already all the Teldec recordings, but only some of the “Ligeti Edition” from Sony… now it’s complete.
Not sure, but I almost think that was the last major “gap” in my collection that “needed” closing. (It was irking me… as I bought the first of these 20 years ago, and by now this was “almost complete” but not quite, so there were a couple of CDs missing… and now I finally got them.)

I have not bought and sold anything via Facebook groups, but I know that there is some trading of film scores going on.