Super easy.
Living in the south, you do not need a traditional 4 walled coop. Ventilation, security and shade are all important to keeping your chickens alive and productive.
I would just frame out the walls. Use hardware cloth instead of plywood for the walls. Add one solid wall on the prevailing wind side, 2-4 nest boxes, a people door, a pop door, a roost or two and you are done.
Security is vital as there has to be a ton of wildlife around you. Being able to free range might not be possible so all that room will make for a healthy outdoor space.
You will easily spend $4-500. Hardware cloth and lumber is still pricey but you are easily saving $2000 with that as a starting point.