Here is my AR so far. Over 1500$ invested. The parts to add to an AR start adding up faster than you think. But I do have a great shooter and I think it looks good. Only thing I may add are some new hand guards. I LOVE the Geissele SSA 2 stage trigger.
Lower - Stag A2
Upper - Bushmaster 20 inch Govt 1/7 Twist Built on a milspec A3 receiver with M4 ramps
MagPul MIAD Enhanced Trigger Guard Aluminum Matte
Meprolight Tru-Dot Front Sight Steel Blue Tritium Green
Harris Bipod Adapter Stud Swivel #5 Black
Badger Ordnance Tactical Charging Handle Latch Generation 2
Geissele SSA Trigger Small Pin .154" Two Stage
Shooters Ridge Rock Mount Adjustable Bipod Sling Swivel
Nikon Monarch Riflescope 4-16x42SF BDC
Yankee Hill Machine Mini Picatinny Riser (2 of these)
ADM AD-RECON Scope mount
Yankee Hill BUIS Flip Rear Sight