I'm in kind of the same situation and recently pondered the same issues.
But in my situation, I have one puck open, I use "occasionally" (well, since I just found it in the back of the closet) and one boxed. I don't want to sell either one. I'm enjoying the open one and look forward to many years of occasional use between the two. So, for me, I would need to be offered something I wanted even more (not an offer and I don't even know what that would be, just saying) if that makes any sense?
I would NOT "charge" someone on this fine forum $100 for it. I would just feel badly doing that here (I know, if someone is willing to pay it and all that, it just isn't me). I would charge them what I paid for it ( but that was some time ago and I have no idea what that would have been)
On the other hand, perhaps someone has something that is "worth" $100 (or more) but they don't want/need/use it any longer. If it is something I think I would want/need/use, I would trade them for it (assuming, of course, they also thought it a fair trade). I'd consider that a win/win. To explain by example, someone has a Simpson brush. They have 40 fine brushes and this one never gets used. I've never tried a Simpson brush and would love to try one. They've always wanted to try Pen EF. Of course, they could just sell their brush. Maybe they'd get $120 for it. But they wouldn't have an EF. Maybe they could buy a puck for $120 and save $20 over this hypothetical trade.... But this is the kind of trade I think would be fair to both parties, valid logic or not.
OTOH, if I just needed the money and didn't care about wonderful future shaves, I guess I'd post it on eBay and let the buyer determine it's worth, to them. I wouldn't feel like I was abusing a friendship, like I would here. (counter argument - someone here could feel badly I hadn't offered it to my brothers here first, I suppose)
How is this different? I don't know. But in my mind, it is. Maybe I need counseling?
Was this helpful? Or just confusing!
Rooney 3/3 Finest, MdC, iKon OSS with Med Preps, AOS AS balm