Welcome, Reinette! Your coop selection depends on so many things. Some want one they can walk into without bending over, so a shed is in order, others want one of the newer styles like the Egglu I think it's called? You might want a tractor style so you can move the chickens around the yard every day or two. Do you live in a neighborhood where there is an HOA? If so that will likely influence your choice.
I have three different coops right now and am wanting to put up another full size plus something for growing out males away from the other birds - hey, a girl can dream! Anyway, my first coop in this iteration of chicken keeping is about 3'x4', the bottom is 3' off the ground, it has an attached run, it's handmade (not by me, I bought it from someone who had decided they didn't want chickens anymore) and because it is up high it's easier to access the interior to check on birds, add bedding, etc. The problem is it's up high and the wind can get under it and tip it over, which it did twice last year, luckily it had no birds inside at the time. Now I have it set up immediately to the west of my second coop which has (knock wood) so far kept it from tipping, since the wind here almost always comes from the west. That coop with young pullets included cost me $400. I overpaid. A lot.
I bought a coop from a gal who makes them from wooden shipping crates, and when it arrived I loved its rustic appearance (still do) but Bob the practical one said, "You can't put chickens in there! It is one big draft!" He was right, there was daylight all over the place between boards. We spent the next 2 or 3 weeks insulating and then covering the insulation with 1/4" plywood, then painting it. Then we also added vents at the top. The original $340 I paid for it quickly grew to more like $600. It is a nice coop now, lots of room (almost 4' wide by 8' long and 3' high, up on 2' legs). It is surrounded by a chain link run including a cover of chain link. It took a lot of work to get it set up the way we wanted it, and just last month we realized in a couple more years we are going to have to figure out how to move it, as there are a couple of young trees that will grow into the chain link.
This past January I ordered the Shed Kit From H*** - paid $2000 for a 12 x 16 kit and spent at least that much again making it right after I had incorrect materials delivered twice and not enough roofing material to actually cover the roof. It was a nightmare - this kit that was advertised as taking a weekend for two people to complete, took almost 3 months. We are fairly happy with it, but when we put up the next one we'll change the layout a bit. It's okay though, I can walk into it, and we ran electric to it so I can brood chicks out there.
Everyone here has their own arrangement, and everyone has tweaked things a bit to get it more to their liking - someone got the coop Big R sells, which is a bit pricey but really nice, I've looked at it (read, lusted for it) many times, and they look well built and attractive. I say "the coop" but they actually sell several, many of which are not so well built. Most of the kits that say they are made of "sturdy fir" are anything but sturdy, they fly around in a good windstorm and just don't have enough room for large fowl.
Wendy can fill you in on an annual tour of coops she participates in, maybe that's a good way to get a better idea of what you want.
Feel free to ask questions and share your experiences - as a group we are all at various stages of keeping, but between us we've seen lots of what can happen when you have chickens.
fl) materials list for phase 3. My hope is to have this final chicken building phase finished by the end of March.... If the weather cooperates......
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