I installed all the windows in the openings of the wallpapered walls. The windows were straightforward to assemble and fit easily into place. At first, I was a bit worried after how difficult it was to fit the front door, but the windows slid in effortlessly. Be sure to paint all sides of the window frames, as it’s hard to know which parts will remain visible once installed. After they are in place, you won’t be able to touch up any visible raw wood since the panes will block access. Paint every edge and side to eliminate any guesswork.