Decoration
Even after building a house from scratch, it is really not done until the decor is done. It is the final and most important finishing of the house. How you decorate your house will play a huge role as to how comfortable you will be living in it.
It is an extension of yourself and you get to express exactly what you are feeling. It can also create a warm and welcoming atmosphere for visitors. You really cannot go wrong with decor since it is art. Art is freestyle and can be expressed anyhow and that is the beauty of it.