I do not own an AR-15, yet. But a good freind of mine as one made by Colt. Ive looked at several for purchase in the .223, and Im going to spend at least $1300 at what Im looking for. However, my buddy has told me that building one is much less expensive. He has informed that I need to start with a quality receiver, and go from there. As I learn about this, Ill chime in with pics. Hope you do the same.