there have been many in that same realm... heck, I know of an action 7 purchased for $20 (many moons ago)...
I picked up a $12K for $3K 2 years ago...it happens from time to time where HUGE profits are available, but it is the exception, not the rule...too much information available these days, if folks bother to do the research (thumbs u
Picked up these two books back in December from different ebay auctions (the MM was an underpriced BIN)...
...under $1K total (yes, that's for both books; no, I'm not kidding).
Yes, good things do happen now and then (it's all about being in the right place at the right time).
I guess this really is the modern version of going to garage sales hoping for the great find.