Oh, no..............we have 5 that graciously allow us to live with them. All rescues. Ours never get outside either.
Our sunroom is only 7x20........zoning would pretty much only not grouse if we squared the house off because we are not far enough back with the house to begin with. Never mind this house is the first one made of wood after man moved out of the caves, so obviously no zoning laws to contend with then. I wish it could have been at least 10x20. But, 7x20 is better than nothing.
It was constructed with the intent of it being a passive solar room. It did pretty good last winter.
Re: budget................We had hoped to get it built for 10k..............har, har, har..............cost 22k by the time we got done.