Brooders: you could get one of the metal battery brooders, that are all stacked up tall.
Here's one example.
https://www.strombergschickens.com/product/five-deck-battery-brooder
But you would have to dump the pans underneath each level quite frequently, and of course it only works until the chicks reach a certain size. So you'd still need somewhere to move them to after that (maybe chicken tractors would work, if you choose the season when the weather is right.)
Or you could get a shed and put in multiple heat lamps, and brood the chicks on the floor. I think that's usually easier. Plan for about 1/2 square foot per bird for the first three weeks or so, double that space for the next few weeks, and by about 8 weeks you should have 2 square feet each. By the time they're adults, plan on four square feet per chicken in the coop or tractor.
If you're only doing it once, you could brood the chicks in the coop where they will later live as hens. But since you will probably need to raise plenty of replacement chicks on a regular basis, a separate brooder space is likely to work better.
You can also use a chicken tractor to brood chicks, although it depends a bit on the weather and the style of chicken tractor. Plan to have reasonably good weather (spring or summer), a heat lamp, and a few tarps to cover the sides (to block wind.) You would probably leave it in one place for at least the first week, and for the next few weeks be careful to only move it when the ground is dry (because a chick pen with a wet floor is not a good idea.)
If you've only dealt with small numbers, I would suggest trying 50 or 100 at once before going all the way to 500. Once those have their feathers and move outside, you'll be able to decide whether you want to do several batches that size, or whether you want to do one giant batch and be done until next year.
Those ideas apply if you're raising chicks that will be laying hens.
For Cornish Cross meat birds that will be butchered at about 8 weeks old, they will never need "adult" housing, so you just brood them until they're ready for chicken tractors, and butcher them long before they are actually mature.
For housing the hens:
A lot depends on your climate.
If you're using chicken tractors, and if you do not have a snowy winter, you may not need a chicken coop for the hens at all. They could just live in the tractors all year long.
If you do need a chicken coop for winter time, I suggest you look into buying a shed or prefab garage or something like that.
Some shed companies also sell chicken coops (a shed with roosts, nestboxes, and a pop door.) But it would be pretty easy to add roosts and nestboxes to a shed or garage. And you don't really need the pop door for the chickens if you're willing to leave the person-sized door open for them to go in and out.
If you're planning to let the chickens go outside each day, think about the weather where you live. If you have long snowy winters, you may need more space per hen in the coop because they spend more time indoors.
In some hot climates, you would do better without solid sides: more like a covered run with perches and nestboxes added. (Or chicken tractors.) You need to keep predators out somehow, but that can be done with hardware cloth rather than anything solid.
If you have warm summers and cold winters, you could have one large building that is the chicken coop in the winter time, but in the summer the hens could live in tractors and you could use that same coop to brood chicks for the next year. Then sell or butcher hens in the fall when they molt, so you have a number that can all live in the coop during the next winter.
