We have two right now, and are pretty happy that way. We've got leghorns who are just laying (okay, one has started, still waiting on the second), and got them as our first attempt at being chicken parents in July. I'd like to branch out one day, but are very content with just the two. They seem to be pretty happy too, since they can wander our yard at their will. And I'm pretty sure they think my daughter (3 years old) is a chicken...they follow her around like she is a chicken goddess who delivers unending bounties of treats.