Manticore, I'm glad you posted the additional details of your thinking, which did a lot to explain your estimate. Thanks for responding to the issue and not blasting me. It's a scary thing to disagree with an expert!
I don't know what the names of the other items you mentioned were, but I think this robe has an especially attractive name for roleplayers in particular. It's generic--that is, there's no reference to a particular shard, holiday, or bizarre event that hardly anyone will recognize--and it lends itself well to being locked down in a house, or worn by an NPC in a house, as part of a tableau. Or, of course, worn by a character with an appropriate, relevant name. Also, it's reported as being unique, and if that's true, I think that makes it considerably more valuable than something where there are multiple copies, even if it's it's just a handful. Finally, robes are more noticeable than sashes, so I think that makes it a little more valuable than sashes. I agree that the lack of a unique color counts against it, but if it's dyeable, I think there's an eye-catching, little-used color could offset that somewhat, enough to draw people to look at it more closely.
I agree that the Scaffold and the Gem of Immortality are not really comparable items. The Scaffold is... weird... (sorry, Voluptuous!
) and probably has very strong appeal to a small segment of the player base who is into.. construction decoration, I guess? And there are very few items that fall into that category, so I expect that the few folks who want something like that REALLY want it, because there are so few items that fit into that theme. And of course the Gem's mind-blowingly awesome reference to the first game of the greatest RPG series of all time--the original standalone Ultima games (not that I have a strong opinion about that or anything--hee hee!)--adds greatly to its value, as you said. (The karma-based message that appears when the holder double-clicks it is also cool, but that coolness is diminished tremendously by the fact that it doesn't work when it's locked down, so doesn't affect the gold value much, in my opinion.) But consider that there are approximately
75 of them across all 25 non-Siege shards, and people are STILL asking 200m for them to this day (and it's worth it, in my opinion.)
So I guess my point is that the robe in question seems to be extra-special in ways that may not have been accounted for by generalized valuation formulas.
P.S.--The "King's Own" sash seemed exceptional to me for two reasons, one being that now that Queen Dawn rules Britannia, a reference to the "King" could reasonably be to our original liege, Lord British, and that appeals a lot to most fans of the standalone Ultima games, I believe. I would love to have that sash locked down beside my in-game "Hero of the Realm" deed from Lord British, for instance. Also, there is a popular series of fantasy novels (Mercedes Lackey's "Valdemar" books) that centers around a class of mage-knights known as "heralds", and one of those heralds always hold's the position of the ruler's chief advisor in the stories. That herald's title is the "King's Own" or "Queen's Own", which adds a bit to the sash's appeal for some people. But not as much as the Lord British reference, I expect.
