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I trust part of your research has been to find out what is legal where you are. Different cities, towns, Home Owners Associations, whatever have different rules. It would be real disappointing to build stuff and get chicks to just have to get rid of them.
Three hatcheries I’d consider have been mentioned, Meyer, Ideal, and MYPetChicken (MPC). I think Cackle may offer some minimum order too but it’s been a while since I looked. As someone said, MPC does not really hatch the eggs themselves but gets them from other hatcheries. All four of those have different minimums and rules. MPC advertises a minimum of 3, but that depends on where you live. For a lot of people, that minimum is really 8.
Meyer, Cackle, and Ideal are likely to include Packing Peanuts with their order unless you call them and specifically request that they do not add any. MPC does not do that though it never hurts to talk to them either. MPC adds some type of warmer to the shipping and they charge you for it. Packing peanuts are extra chicks thrown in free of charge so there are enough to keep them warm during shipping. These are practically always male since that is generally what the hatcheries have extra.
You need to put your order together online to see what the costs are. Some have things that can add up. If I remember right, Ideal will ship small numbers of different breeds, but they have an additional charge for having different breeds. Look for things like that.
This is a link to the sticky in the Breeders and Hatchery section of this forum. You will find some positive reviews and some negative reviews on each and every hatchery. Each hatchery is run by different people so there will be some differences, but some of those negative reviews come from things not in the hatchery’s control. Either something the post office did during shipping or the person receiving the chicks was not really prepared. Some of these hatcheries ship 80,000 to 100,000 chicks a week, so they will occasionally mess something up. The post office usually does a good job too, but occasionally they mess something up. You are dealing with living human beings. Sometimes we all make mistakes. I would not be concerned about ordering from any one of these four.
There are different ways for you to try to get a variety instead of ordering from a hatchery. There are some potential problems with some of these, like if you get chicks you might get some roosters which I’m sure you don’t want.
You can look up the Illinois state thread in the “Where am I? Where are you!” section of this forum. It’s quite possible you can find someone local that can help you out either with baby chicks or maybe started pullets. Started pullets may be one way to avoid roosters. This might be a good way to find someone local to split an order.
Check out your feed stores. Many of them will be having “Chick Days” before too long. Orscheln’s, Tractor Supply, or maybe some type of Co-op are some of the possibilities. Talk to the person ordering the chicks to see what options they offer. Each one is different. Some people think because their Tractor Supply offers chicks a certain way each one in the country does it exactly the same. That is an incorrect assumption. The feed store may let you place a specific order and just add that to theirs so you can get around the minimum that way. My local one does not offer this. Some will have special pullet bins where most of the chicks in that bin are pullets. Some just have bins where they are mixed by sex. Feed stores generally get their chicks form hatcheries. Hatcheries guarantee a 90% rate on sexing the chicks, though most hatcheries will not sex bantams. So it’s real possible to get roosters from pullet bins. A lot of that depends on how good the Feed Store is about keeping them separate. Anyway, talk to different feed stores and see what they offer. There is a chance you can find one that will help.
You can order a bunch and try to sell the extras on Craigslist. You may or may not get your money back.
There are probably some chicken swaps or such in your area. Again, your State thread may help you find these.
You can call your county extension agent, in the phone book under county government, and explain what you are looking for. Some extension agents are better than others and some have better contacts than others, but there is a reasonable chance they can help. It costs you a phone call and a bit of time to maybe find out.
Good luck with it and again,