Selling old black holder NGC coins to forum members......my experiences.
Going back quite a few years on the PCGS forums I've sold a total of 5 old black holder NGC coins to various forum members (1 coin to one guy, and 2 each to two others) with the condition and gentleman's verbal agreement at the time of sale that should they ever decide to sell the coins anytime down the road that they would let me know and give me first shot to buy them back. In each case the three various forum members all agreed and said that was fair and I took them all at their word, These coins were all sold back when the old black holders still brought a premium but of course nowhere near the absurd money they bring today when rarely offered.
So here's what has happened since and my experience with taking people at their word...... forum member #1 that bought 1 coin didn't last very long and flipped his for a profit without giving me first shot as we agreed, and when I called him on it he apologized. Forum member #2 that bought 2 coins lasted a few years and then I saw both coins in Heritage auctions. I also called him on it and he never responded to me and some time afterwards he stopped posting here. Forum member #3 who also bought 2 coins lasted the longest and I've only just recently also saw 1 of the coins listed at auction, although I have no way of knowing who consigned it and if was the same person here who bought it from me or if it's traded hands since.
I would also mention these are / were all highly regarded long time forum members who I thought would honor their word at the time. So the moral of this story is.......well, you can decide that for yourself. I still have a couple more old black holder coins that I purchased from a local dealer when they traded for no premium, but will not offer them for sale privately anytime soon. Also, I sold the coins on the old forums when my forum name was dragon and then later quit the forums after a private email dispute with the then president of PCGS over a submission and later rejoined with my current name after he left PCGS.
Your hobby is supposed to be your therapy, not the reason you need it.