mjkeat, is right... if your budget is $800 for entry level, why not aim your sights a little higher and get all the gun you need. It will cost you a little more but your real investment is research and a lot of it if you don't want to make blunders. If you do your homework there's no reason why your first AR can't be all you need, if not all you want.
Right now is a good time to buy, overall high quality by many manufacturers, good prices and shorter wait times than in the past. I just built an AR that's all I need for about $900 (before optics) with high quality parts and the configuration I wanted.