Bruce, if the item was consigned to me, the seller would get $77 from me at a $108 sale
similarly, on your $144 sale, the seller would get $103.
the bigger difference however might be the time frame it would be sold. I have listed consigned items literally the day they have been received in the mail in some cases and we know it could take quite some time before you would get the poster out for sale and that time can be considerable, especially to someone trying to raise cash right now. So there are benefits on both sides of that equation. $77 now, or $103 in a period from a few months to "who knows when" (not ragging on you Bruce. just stating the facts)
However, seeing as I owned the poster and it sold for $108, I got $5 more than I would have gotten from you (had I consigned you the poster) and I have the $$ now, not later. All things being equal (like saying the consignor to you and myself were equally invested) for me, I am in the + (PS: I only had the poster for 1 week prior to listing it, so in this case my consignor (myself) got to market super-fast and got his cash faster.