I like the tractors - very neat - no odor. A lot less mess. That's not to say there isn't maintenance cause there is. Wind blows rain in the sides and the feed gets wet. I had to have plexiglass cut to fit the sides so to protect the feed during all this rain we've had. I actually had them cut this winter to help give the birds protection. We had a lot of snow. That made life with a chicken tractor very hard - on me and the birds. Too much confinement. Too much exposure to weather. In the end we put the tractor in the middle of a 10x15 6 foot high kennel fencing and covered it. Tarp fell in from weight of rain. Then we built a PVC pitched roof over it and covered it with a tarp. That worked mostly, but I had to go out in heavy snows and push it up to knock off the snow so it wouldn't collapse. It was nice to have something covered to be under while caring for the birds but it was a lot of work. I couldn't wait to get a real coop. Which is what is happening right now.... hence the treat on our building.
My birds will still use the tractors occasionally after the coop is built. I free-range my chickens 2-5 hours a day. But there will be days when I can't and the tractors will come in handy.
Thanks for the comment I'm debating i live in the city limits not wanting to build in buildings our building inspector here is something I can say being a Pastor. I had them in a dog kennel coop, we are having some storms came in from church to find my chickens on the ground and my pen in the trees behind them
I have one with tires and a floor for fuzzy butted tweens that will hold birds until our weather breaks and allows us to move them outside on warm days and into the garage when it gets cold. Also allows us to do the same in the fall to postpone butchering.
I have friends with open floor tractors and they move them around their yard allowing fresh bugs to be eaten and manure dispersion as well as their natural scratching's benefit on the ground
We have a tractor for our 8 hens. Works great (you can see it on my byc page). It has a portable run and a floating skirt. We move it around the yard every day or every other day. It is very secure against predators and weatherproof. We had an unusually rough winter this year with lots of snow and cold. The girls did fine. Its an 8x4 tractor. They were locked in during storms and no problems or issues. Food and water is kept inside all the time so the girls can eat and drink when locked in. The pop door was open every day except storm days and they could choose to go out or stay in. Most of the time they went out. (They were pounding on the door and yelling at me through the vent to hurry up when I was shoveling out their run. Bunch of pushy nags!!!) The tractor is on wheels and dh and I move it. Our yard is very uneven and hilly so thats why a floating skirt. You have to look at your terrain, predators and decide what works for you. Mine are always locked up at night and only a bear or human will be able to get in. We have lots of hawks so the top of our run is also covered in wire. I do let them out to freerange every evening and am always right there with them (along with my dog) to be the predator deterent. We have had some heavy storms from time to time but this thing doesnt move. I hope this helps.
For some reason I can't find the pictures of the modified A-frame tractor I built. Mine has a bottom foot print of 5'x5' but you could make it any size you want. As soon as the rain lets up I will take new pictures and post them for you. By making the roof flat rather than coming to a point you add considerable headroom in the coop.