If you're in a suburban area, the assumption is that you've checked local ordinances and roosters are legal. They can be very loud and many people don't like roosters. They are not allowed anywhere in our county - although people do have them from time to time as we hear them at a distance. Be sure they're legal first.
The typical recommendation ratio I've seen here is 8 females to 1 rooster.
Build your coop and run to accommodate the size flock you will end up with not what you will start with to avoid having to add on or enlarge it later.
Minimum 10 sq. ft. per adult size bird for run space, excluding items you have in the run that take up space, i.e., perches, feeders, waterers, etc. Minimum 4 sq ft per adult bird for roosting is what is recommended.