I just built two and you'd think that it would be cheaper to by a complete rifle but a complete rifle is subject to an 11% federal excise tax. In my case I wanted the absolutely most bullet proof AR15 that I could afford. I think you'd have to buy a
Noveske or a Colt to top this and that's without the Geissele trigger.
Here is my build list minus the EOTech:
Bravo Company 16" middy upper $480
Bravo Company M16 bolt carrier group $160
Daniel Defense Omega 9" rails $260
Troy folding rear sight $140
DoubleStar Stripped lower $120
G&R lower parts kit $40
Geissele SSA trigger group $170
Magpul MIAD grip $35
Vltor EMOD stock $180
Total $1585
Now realistically you can shave $140 off that by buying cheaper rails, and shave another $150 off by buying a DPMS lower parts kit with a GI trigger and a GI pistol grip. And you can shave another $100 off by getting a Bravo Company carbine stock kit. Total for a rock solid AR but without the deluxe add-ons $1200. More than it would cost you for a basic
Smith & Wesson M&P15 and about the same as a nearly comparable Smith.
Sources:
G&R Tactical