How big should a chicken coop be?

Plan 3-4 sq ft inside the coop and 8-10 sq ft in the run per standard hen. Bantams need less; heavy breeds like Brahmas need more. The planner sizes this automatically based on your breed mix and climate.

How many nest boxes do I need?

One nest box per 3-4 laying hens is the rule of thumb. Hens often share favorites anyway, so adding more rarely changes laying patterns.

What's the cheapest way to build a chicken coop?

Repurpose a garden shed or pallet structure, but never skimp on 1/2-inch hardware cloth, a buried predator apron, or roof-level ventilation, those are the parts that keep birds alive.