I have to agree.
My opinion is that if you have a limited budget a manufactured machine is the only way to go.
When I built my system, I thought that by selecting just the right hardware I could get a system cheaper than a pre-built system. Since then, I have seen less expensive machines with most of the same or similar hardware (mostly they just lack an SSD). I probably could have gone with a pre-built system, added what I thought it needed, and saved $50 to $100.
In the long run a self built PC is much better as it allows for flexability in upgrading and will end up costing less since you can throw more parts at it than a manufacture built PC.
But as everyone else is saying, you are going to need a bit more of a budget to buld one your self. I would say $700 or so. I believe my first PC I built cost me $750. I would say save up a couple hundred more then get your parts.