Living Room, Concrete Floor, Sofa, Coffee Tables, Chair, and Rug Floor The built-in sofa was designed to be very functional. The base has storage capacity and the mattress is the size of a single bed for an extra guest. Plus, industrial grade foam and fabric ensure the cushions will hold up to wear and tear.   Photo 5 of 9 in You Won't Want to Leave This Cozy Cabin in New Zealand