Ok, now I put a full set of dragonscale and a full set of dragonplate armor on my dummies in my house in solitude, went back and they are gone.

Anybody know what happened?

It wasnt me. I was in Rifton at the time and have people who will vouch for me.

See, this is why I never trust Brits.

Now I seem to have picked up a grand staff of charming and I can't get rid of it. I try to store it and it says it's a quest item. I saw a thread elsewhere that said to take it to elgrim, but that did no good. It's not stolen.

Did you click on the dummies to make sure it wasnt there? sometimes it will glitch and go invisible but will still be on the dummy

People say "some" but as far as I know every mannequin in the game is broken, for sure every one I've tried which includes proudspire, hjerim, honeyside, and DB master bedroom. The usual issue is when you put armor on them they disappear from view, and they tend to make duplicates if things you put on them (i have 5 Ebony Mails and every so often another is created by a mannequin in hjerim).

However I've never heard of them making items actually go away and not let you retrieve them, or five of them.

My mannequins seem to like to walk around my homes while I'm not there. I still have to activate them where their bases are, though. I'm guessing a lot of the problem comes from (what I'm assuming) having to make them NPC's to get them to wear your items. Almost like the statue of yourself in Oblivion in Bruma that you could get to glitch and come to life. Maybe the mannequins have a routine to follow when you aren't around.

My manequins are all just fine! I have the 3 in Hjerim and the 2 in Proudspire and no issues with any of them so far.

At Hjerim I have my Nord Civil War Museum with full Stormcloak and Imperial manequins, as well as a full Al'akir (w/ Curved.Sword in a nearby case) from Whiterun.
At Proudspire i have the Dovakiin guy from the advertisemants in full get-up as well as an ebony set waiting to be upgraded/enchanted if I ever feel like using something more dark.

No problems so far, fingers crossed.

I've also never had a problem with mannequins. Lucky I guess?