I have one that has second poop doors on several sides, with a run that I am building with a skirt that latches on to the side. Thus, I can move it around from side to side to let the ground rest without moving the cool for when I can't free range. It is planned to be three feet high with a skirt that is screwed on with two by fours to move easily.Yeah, Ive seen what they call "combination coops" with an underneath area under the coop. Its hard and expensive to make a run, so it is smart to make every sq ft available count. I can't have chickens free range where I am....too many hawks. So they have to stay in an enclosed run all the time. It gets dirty and cramped in there with too many birds, so it really sets a limit on what you can have. I will have to look into this method. It seems like a good idea.