my 2cents.
sell the emanage and buy a real ecu; after seeing the issue all-star had with tuning one i would stay away from them.
Installing the GT-RS is easy job, i did ztuned for him took afew hrs. the kit inc. all gaskets needed (if i remember right) machining of the manifold is not needed, so tell them you don't want it done.
Injectors can be a time consuming job, i pay $350 to have mine installed by EVO-R, was quoted around $600-$700 by other workshops. If you got the tools you can do it yourself just takes sometime (can be done without removing the plenum but takes longer)
Tuning cost is anywhere from $500 to $1000 depending how long it takes to tune (if i remember right most people charge around $150/hr for tuning)
So EMU install (nothing, they just plug it in) $0
Tuning EMU $500 - $1000
Injectors $350 - $700
Turbo $500 (ruff est, @ $100/hr for labor and 5hrs)