if you want it to last, build it or have it built. Most of the commercial coops only last a couple years. How much room do you have? are your girls going to be free ranging, are you planning to have broodies raise chicks? Lots to consider.
Welcome to BYC!
We are glad you joined our flock.
This video should help your find your way around.
A great place to start is in the Coop section in the Articles section.