Looking for recommendations

I'm looking into getting my first gun. Figured an AR was the best option, but im something of a novice here on what actually makes an AR good. I was looking at palmetto and have no clue aside from price which models were actually worthwhile. I saw some as low as 400 but that seems too good to be true. Also if there are any unobvious purchasing pitfalls I should be aware of please do tell.