congrats on the new coming hens! You must be thrilled...It's so exciting getting hens...I would get 10-12 for the size you're going to have. Also if it's the first time,you don't want to get too many and become overwhelmed. You can always add more as time goes on :)
Good luck!

Yes, although with a large run, you could probably double that number, you'll be busy cleaning the litter all the time if you do....... and it would be a handful until you get used to their idiosyncrasies. Brooding them out takes a bit more effort, and a dozen is easy for a beginner.

Congratulations, I've had my flock for about twelve or fourteen years now and have enjoyed every minute of it, not to mention wonderful, fresh eggs and sunrise serenades by some great roos.

You don't want to over-crowd them and all the books say you need anywhere from 2 to 10 square feet per chicken. I find that 4 square feet of floor space per chicken is fine. So with an 8'X 8' coop, you could theoretically have up to 16 chickens if you go by the 4 sq. ft per bird.

Better to have too much room than too many hens. The large run will stay in good growing condition with fewer birds. This also means less health problems. Outside flights that are overcrowded tend to not have anything growing and become nasty when it rains and are of no use except exercise. Ask yourself-how many eggs will you need per day. 2/3 of your flock will lay per day on average. During spring and early summer you'll probably get close to 100%-but when light levels fall so does egg production. There are many ways to do this and the only one that will work is your's. Good luck and happy chick'en!