I am considering building my own AR15 rifle in 223. I have been reading up on the process and doesn't look that tough. I see there are a few tools I will need to buy. When I roughly added up the parts and tool costs, before shipping charges, it's pretty much the same as buying the rifle. The model I like is S&W M&P15MOE which I can buy for around $1000 assembled. I'm sure it's something I can do with the right research, but will I even be saving any cost by building it myself? Thoughts?