Every dollhouse is different. Each one has its own way of being built. So there are different approaches. The first is to build the house completely and then paint and paper the walls, finish the floors, and turn the house on its roof line to paint the ceilings. A second way is to prepare all the walls before final assembly. Last, a mix of approaches, depending on the type of house. For example, some people may assemble the house, only decorating the hard to reach spots before assembly then decorating the rest after assembly. It depends on you and the house. I chose to decorate before assembly. If I build another Pierce, I will choose paint or paper on various walls differently. I abhorred the idea of light shining through the cracks in the wall joints. So during assembly I clamped the walls together so tightly, it created problems later on for the roof assembly. I think the value of papering two adjacent walls after assembly is that those joint cracks would be covered...