Here are some pictures, sorry it's overdue for a deep cleaning (and repainting), so dust and cobwebs! Hope these help and maybe give you some ideas. I'm always modifying, and will again this year, I'm going to add more windows to my large clean-out doors on the back for increased ventilation, though my ridge vent helps a lot.
Here is my coop and enclosed run, you can see my solar panels in the back right. I plan to add a couple of panels in the future for a bit more power, in the summer when all fans are running all the time I run a trickle charger to help right now. I can go several days with no power at all currently. In the winter I don't have to run the trickle charge at all.
But I have 3 fans, the light and my automatic door on it.
Here is one of two window fans, they are mounted outside and blow out, one on each side of the coop, you can see the other on the other side in the background. They are sufficiently protected from rain that I've never had a problem. They are mounted to the hardware cloth with cable ties so I can take them off and clean them, I just replace the ties.
This is the larger fan in the peak of the coop, under and slightly to the side of the ridge vent. The light is an LED bulb on a timer. The fan is on a switch so I can leave it on all the time or only as needed. Timer for the light is on the wall to the right of the light, just out of view. These are all out of reach of the chickens when they are roosting.
Panels from the other side, wires are cable tied and wrapped along the top of the outside open runs fence.
This is where the battery, charge controller and trickle charger are mounted, in the eaves inside the covered run.
This is my timer for my automatic door, at the far end of the covered run. It also is wired to a light sensor, but I never use the sensor anymore, just the timer. A dark nasty thunderstorm would shut the door when using the sensor. The timer in the coop for the light is basically the same kind.
Just below the timer, my automatic door with it's fancy rubbermaid protection from weather since it rains sideways here sometimes. We just cut the one long side (short side?) off, and put foam insulating tape between it and the frame. The outside of the door is enclosed by painted plywood, so no weather has ever gotten inside it.