I almost negotiated a purchase of some really nice coins from a CCF member (one was a CC mint Morgan, not sure what the others were) when I got too busy (can't recall the details) for a few days, and before I could reply again the coins were on
ebay.
Now, I don't have an
ebay account, a PayPal account,
or a credit card (I might have that last one now, it's a bit confusing - but I definitely didn't back when that happened). Most money transfer options I could think of were specifically disallowed by
ebay - even assuming I could somehow set up an account (which in itself was a big question) - and the remaining ones (that I could think of) went into two categories: either "let a friend buy the coin for me" or "um, the money should reach the seller in a few months if we're lucky" (and I suspect most of the stuff in the second category was only not specifically disallowed by
ebay because they didn't expect anyone to agree to it).
By the time we figured out
that, some of the coins were sold, and the others went up to beyond what I could afford. Good news for the other CCF member I suppose, because at the end he got more money; bad news for me, because I could barely afford
that CC mint Morgan, and between it being about the lowest grade they get and the exchange rate more than doubling since, I probably won't be able to afford another unless I save up for it specifically (and perhaps not even then).
...On a somewhat better note: there was that one guy on the Vernisage who was selling
Liberty nickels for (what was then) $6 each from a bargain bin.
The bin was full of 1900s dates, of course, but there were a few worn 1890s and 1880s in there too. I pulled out one of each 1880s date I could find (including both 1883 types, IIRC), but mostly ignored the 1890s, because I didn't remember if any were valuable.
Sometime later, I remembered that one of the 1890s was an 1894. Argh. And the next time I went to the Vernisage, the bin with all the nickels wasn't there anymore.
Later on, the same guy (if I remember correctly) had a different, $3 (or $1.5? can't remember what month it was) bin with all sorts of world coins, including a lot of silver
War Nickels.
I bought the best example of each date I could find (9 or 10 in total - I don't think I had all 11 versions), including the 1943-D.
One 1943-D. There were at least three 1943-D nickels in that bin, and I let two of them go by.