"I got outbid at the last minute."
That is unfortunate because that was an extremely good deal. Good deals are available on eBay despite what one guy says. I know for a fact because I have sold lenses on eBay and they were in like new condition and about half price. You were outbid because somebody else beside me saw it as a good value. If you are going to use eBay you have to watch it carefully when you find a good buy. Because others will also know that too. Is there junk? Certainly but you got personal advice from a person that has bought and sold many, many lenses, for whatever you deem that worth.
"... one 150-600 went within $99 of a new one; it was described as scratched and scuffed and no return."
Don't buy that one!
"This the only photography forum that I frequent."
Even here you can get steered wrongly.
"I always found that to be good advice."
Perhaps so but you need to strike when the iron is hot. Who knows where the EF market will go as it becomes depleted. There will be, and likely has already happened, no more EF gear made. Yet there are millions of EF cameras out there that are not going to die tomorrow. Lenses like the 150-600mm don't wear out easily and are good buys used. Some folks maybe most don't put them to much use. They find out they are heavy and big and require some thought so they sit. Folks finally decide to get rid of them after they hold down the shelf in the closet for a time. Now of course there is the junk and abused lenses to watch out for. That's on you.
EB
EOS 1DX and 1D Mk IV and less lenses then before!
