hey guys, I met a guy at the range and after talking for a bit i mentioned i was looking to build an AR. He told me he has a stripped upper assembly, with only about 500 rounds through it, he isn't using and would sell me. Its from a M&P15 sport so it doesn't have a dust cover or forward assist but from my understanding its a pretty decent barrel? It also comes with a quad rail and a detachable carry handle. He told me to get back to him if i want it, but this is my first AR build and i'm not very knowledgeable on prices. I'm just wondering what you guys would value it at? I'm very interested and excited to start my build but i dont want to overpay:huh: Any advice or price estimates are GREATLY appreciated.