Well I remember not too long ago there were many more on C24 than today and prices seem to be creeping up.
You can still find them of course but the classic cases more readily available. I have wanted a Square to complement my Origin opaline but I’m not sure it will be happening anytime soon.
New they go up, but even used it seems, based on public listings which naturally does not equal actual selling prices. I remember not too long ago, I saw several squares on C24 between 30-35k and I don’t see that anymore.
Anyway, let’s not get into a pricing discussion here (however interesting!). This bright blue you posted is for sure a watch that I would love to own. Very striking piece.
These 2 pics are of the same watch
And the watch differs from the one that you've posted by a case shape. The dial color seems to be the same.