r8 max blue Butterfly Mirror - I'm thinking no more than 10-20k, not sure. Mesmer stuff is often hard pressed to find buyers. :/
15/7 command blue Skull Shield - I'm thinking this could still hit the 60-80k range, maybe more. It seems like you do see quite a few of these around, but they also seem popular enough to keep their prices up there.
16/8 tactics blue Adamantine Shield - I'd expect bids would take that over 100k, but I'm not sure.
16/8 motivation blue Vabbian Bastion - really hard to PC. Motivation doesn't seem to get anywhere near the same kind of love as Tactics or Command do right now. I'd pick a price I was comfortable letting it go for and just see what kind of offers I got. Maybe s/b 30k and see where it goes? The skin does have its fans lurking out there, I'm just not sure how Motivation will affect it.
16/8 Command blue Aureate Aegis - That skin is one of, if not the most popular Paragon shield skins for caster shields. I would not be surprised to see a bid war take that well over 100k. Were it mine, I wouldn't even consider letting it go for less than 70-80k.