Improvements and themes can be bought from Moira for My Megaton house or from Lydia Montenegro for the Tenpenny Tower suite. If one lets the ghouls in during the Tenpenny Tower quest, Michael Masters will be in charge of improvements for your suite. Despite this, Godfrey will still advise you to go to Lydia Montenegro, even though she is dead.
My First Infirmary
My First Laboratory
My First Workbench
Pristine Nuka-Cola machine
Love machine theme
Wasteland explorer theme
Each theme is 1414 caps, but the price lowers with a high barter skill.
The theme purchased last is marked as a quest item and cannot be dropped or removed from inventory.
Skill books, clothing, and other items appearing in themes can't be respawned by reloading the theme.
The house/suite can be decorated by placing items around the house.
The Tenpenny Tower suite is sometimes accessible via the door on the balcony without having first blown up Megaton or been awarded a deed of ownership to any housing.
Once the deed to the Megaton house has been received, Godfrey (the Tenpenny robot butler) will have the same talk options as Wadsworth. Prior to that point he cannot be interacted with.
The Tennpenny suite upgrades are only available if Megaton is destroyed.
Any bobbleheads placed in a collector's stand will only be viewable on the stand where they were placed, and are not viewable in both player housing locations.