OK so like i bought a new how in windhelm and it took several trys and reloads to get the decorations to even all show up sometime they would act like i bought them when i did but then i would go to the house and they would not be there examples are blood and body still on floor even thought i bought the decoration to clean up the murders mess for 500 coin. but when i did get it to finaly all show up in my house after way to many try it took forever there were still problems such as i cant mess with the weapon racks to put my weapons on them or the decoration wall thing to put shileds and weapons and such on i cant mess with just like the weapon rack when i look at the weapon rack or wall decoration areas it does not say press a to activate .
i also have problems with my house in whiterun when i try to use bookshelves i can use them once and then i can take off my books and such but can never use the bookshelf again
I have the house in Riften and if i load my saved game inside the house all the furniture vanishes leaving all the stored gear on the floor takes a couple of reloads to get back to how it was when i saved.
Its a bug with many of the houses unfortunately but I think they know about it as its plaguing a lot of us.
Also be very careful using mannequins and book shelves as the can delete your stuff. In fact I would not bother using them at all until a patch sorts them out.