The third one is 6 feet long and 3 feet deep. It is so heavy that we cannot move it easily. The good news is that I can always convert it into some storage thing, by just adding doors in front.
The second one is really easy to make and to move and I love that you can simply tip it over to clean underneath. I actually love it so much that I will make another one. Today it was down to 22 this morning when I let them out. I can see the second and first shelter from my office window and they are having fun in it. No snow yet, but it is nice to know that they have a place to get their feet off the cold ground. The plywood one could be made with cedar slats too. Would cost a little bit more, but would be appealing in looks.