After building Windspeak manor I erected an armory, bedroom and storage room. (Giving the background here). I fitted my mannequins with armor including the assassin guild leaders shadow armor and peripherals which I wasn't using at the time. Later I came and picked it up for a quest, when I got back that mannequin had a full duplicate full set of shadow armor which I then sold for a good profit. After taking it down I replaced it with dragonscale. The next time I went back it had sprouted another suit of shadow armor. The dragonscale was still on the mannequin, just not equipped. That armor I took and sold also. Am considering going back and putting the shadow armor back on that mannequin and seeing if it'll sprout again just for the fun of it since I have more gold than I can conceivably spend in-game,