there are meat birds and laying birds
from the time you have them as chicks to the time they are full grown and start producing there are 3 standard setups I am familiar with
1. the box.. which is basically any topless and four-walled box structure with a heat lamp and plenty of straw. at this early stage they are sensitive to heat and cold and liable to get ill for no apparent reason and die
2. the cage on skees .. this is good for when they get a little bigger / sturdier but not big enough to lay anything or crowd the cage and look miserable. usually a low-ceiling, 6x6, floorless coop with a tarp zip tied over half of it for shade and cover. it is designed to be lightweight but heavy enough that a coyote or skunk can't push up under it. you drag it over another 6-7 feet every day or so for fresh grass. among materials often used I've seen a mix of pvc, solid steel and or two by fours and either a cattle panel arched over for the top or just straight chicken wire all around. the door needs to be on top or big enough that you can get at the food dishes and adjust water buckets / etc.
3. the caravan .. this is a mobile coop, for the most part floorless but lined with size large chicken wire, gauged so that a large rat wouldn't be able to climb in but chicken shit can still drop out and not build up in places. one long center beam through the length of it for walking on and plenty of sticks/staves for roosting. seems to me any sized flat bed trailer would serve as a starting point, and from there tearing off baseboards and cutting out any steel railing in places it would be useful to in order to add on the rest. it is the same concept here as the cage on skees.. that with mobility and no flooring you save yourself all the hassle of forking and scraping out a ton of rotten straw every month and at the same time fertilizing the soil below.
once fully grown set a stretch of electric poultry netting out around your chicken house (not failsafe way of keeping them contained but it helps alot if/when rigging up a whole area top to bottom with wire isn't entirely necessary), opening and closing the door to the coop every day.
what else,,, they'll take to squash and other fruit or veggies otherwise going to compost but no citrus.
also, chickens will stop laying eggs altogether under stressful conditions like scarce food or overheating due to poor shelter or hydration, and won't continue to do so again until long after things are corrected. could be months.
eggs will keep nearly a month without refrigeration, maybe less if left in direct sunlight but generally.. yeah