An old turntable, a bunch of cardboard boxes, a few sheets laying around, an old bicycle, a broken upright lamp, a table with various outdated trinkets on it and whatnot
We love the turntable idea. The old bicycle is nice too.
extra paint cans for chipped walls and all that jazz
Paint cans are interesting and new. Not sure about that yet.
sekret hiden safe
As much of a joke as you meant it to be, it seems like a cool idea. The house will have many secrets in it for sure.
a pool table
Although it was my FIRST item that was going to go up there, we already have a room dedicated to novelties like Pool and Darts. A spare piano was placed into the attic, and it seems odd to have a spare pool table along with the other spare "things" that are already up there.
Matresses.
if its a room thats meant to be used, you can make it some sort of workshop.
a bed next to a nightstand with a candle on it, a desk in the corner with a globe, some wood and paper and cabinets.
Mattresses. Huh. Maybe.
The room already have a desk with a globe near the telescope. It's like a nice stargazing office-type area. Good idea though!
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To everyone else, the ideas are nice but just don't fit. Christmas things just won't go well in this creepy old mansion.