It will be a more cost and time efficient to focus on getting a good run installed. You can still let them free range and forage whenever someone is around to keep an eye out for danger. Then worry about the perimeter fence. And flying predators are a constant threat unless your run is covered...
Step One - Get a run setup. Some welded wire fencing and metal posts will do. Adding a few strands of electric wire around the top and the bottom should be enough to stop those dogs. Netting or strands of 'flash' tape will help repel aerial predators.
Step Two - bigger coop for all.
Step Three -...