The cage, all that great aero, nice flares, air jacks, cooling ducts, alpha-locks, etc, etc, etc... so much bad ass stuff going on here. The fab work looks top-notch. Really nice build.
If you have the time, skills and machinery to do the whole fabrication and work by yourself, it won't be very expensive. However, if you would hire professionals to do it, it's gonna be extremely expensive.