i was browsing thru craigslist when i found an add for "4 free hens,about 6 months old,very friendly" i figure yeah right,but i call anyway. long story short the lady bought them this spring at tractor supply and is moving and cant keep them. so im going monday to get them!! well,unless they are all gross and sickly!! anyway i know i need to keep them separate for a month,but my yard is not big and i let my flock free range.is there a certain distance i should keep between them? should i keep my flock contained also for this month? since they came from a hatchery will they be vacinated from most disease? and what should i look for for illness they may have? thanks for the help and advise!!