To me, to make a profit on boards, about the only things worth refining myself would be fingers, pins, and certain CPU or other IC packages. I say this from experience. The boards themselves I wouldn't touch with a 10 foot pole except to evaluate before selling them. I would then sell them to, say, Boardsort, or eBay. Just remember the eBay charges. I would guess that Boardsort is paying about 50% of value on that sort of stuff. To me, this is very fair on such low grade stuff.