I realize that this thread is probably irrelevant now, but I just thought I would still comment. I had a rabbit whose cage was too small and he lived outside. We made it to block him from the wind and whatnot and I kept asking my dad to build him one. Well, It cost the same amount to buy one but building it gives you a wider range of options on how to build it. I'm not even joking when I say this, but i literally FORCED my dad to build the cage since winter was coming and if he didn't do it now, he would never do it. Well he build it. It was 2x the size of the crap metal one we bought originally and he had an outdoor area and an indoor.. he always pooped over a pan we got from tractor supply so the front area was the eat & business area. This summer I want to finish it by completing the bottom portion which he can always go down to and dig in the dirt (theres no grass in the shaded area hes in)
Anyways, I recommend you try to eventually make something like that because it can go YOUR way for the same amount of money and be better suited for your rabbit. Remember that I made mine for 2 rabbits so it was doubled in everything.
But chicken coops are good if you have 1 rabbit, or they dont fight at least. As long as they have a little hidden house (w/ tile in the summer & shavings in the winter) he can live outside, ESP. because hes a big breed :)