Hi and welcome to the flock. Glad you are here. The biggest thing is research: coop design and run arear. Chickens: dual purpose, egg layers, colored egg layer, cold/hot hardy, bare confinement well, good mixed flock bird, gentle and quiet. It took my a year for me to decide what a wanted. Good luck!
Good for you for researching first!! I started with a prefab, but I would not suggest getting one for any more than 2-4 birds that free range daily, even the extra large coops are pretty small. Their descriptions are very deceiving. There are some kits available that are a more suitable size and do not come with an attached run... those are better but very expensive. Modifying a storage shed can make a great coop!
and Welcome to Backyard Chickens. 
to have you here with us. Enjoy your time with us at BYC!
