I bought one of these
https://nestera.co.uk/
and am entirely happy with it; indeed, as the flock has grown I have bought two more of them.
My principal reasons for choosing this material, design, and manufacturer are
1. essentially no mites. The interior surfaces are smooth plastic, so there is almost no-where for them to hide. When red mites arrive (as they do, especially when it's located under a tree) they are easy to remove; see 2.
2. It is trivial to clean with water, no chemicals needed. The whole thing disassembles in about 15 minutes, can be power-washed, and reassembled.
3. It is mobile. I move them to new ground regularly, so there is no build up of disease in and around where the flock roosts and lays.
4. It is rat- and predator-proof, at least for the predators we get here. The thick plastic is at least as tough as the sort of wood I usually see used to make chicken coops.
5. It is made of recycled plastic, so good for the environment.
6. It holds its value so when I have to stop keeping chickens I will recoup most of the capital investment made at the start of my chicken-keeping journey. This make rarely appears on the second-hand market, and when it does, sells fast, despite being priced close to new.