I have a locally-built version of a catawba coop. It was really inexpensive, but if I had to do it over again, I wouldn't do it.
It is heavy enough to last but only takes 2 people to move.
For predator safety, I added a wire skirt and that hinders moving it as easily and I have to stake/unstake down the skirt at each move.
We do allow the chickens to free range for a few hours daily. With only one door access to the bottom, the chickens charge the door to go out when I only want to change the feeder and waterer.
I live in Florida and I find the upstairs area is probably unbearably hot for the chickens even in full shade. No ventilation. We had a special frame made with 1/2" hardware cloth to fit upstairs to cool it off a bit, but it is not predator safe.
I have six 7 week old chickens in it now, but I really can't see more than 3-4 large breed chickens being happy in the 8 foot long tractor. I might have another coop built soon.
My chickens eat every single blade of grass under the coop in 24-48 hours, so soon I won't have any grass left in my smallish backyard. I find free-ranging to be a better choice to keep damage limited to manageable amounts, which kinda negates the reason for a moveable ark/tractor.
I will definitely keep this tractor in case I ever need to separate my chickens for whatever reason, or if I ever have youngsters that need to be integrated with older hens. But, I don't see myself using this design indefinitely as my girls grow up.
Just my 2-cents!