There's also nothing worse than having 1/2 the work by one person and 1/2 the work done by someone else. That leaves a lot of room for finger pointing and a lot of room for people not being able to take responsibility for certaIN THINGS BECAUSE SOMEONE ELSE TOUCHED THE CAR (whoops caps). I don't know how many times someone has brought a swap or a turbo install to us and said " I have the engine in the engine bay, it just needs to be finished up." Sometimes it costs 2 x's as much as it would have to just let 1 person touch it. If there are issues along the way, it's best to have one persons hands in the pot so he can back track thru his own work. It sucks back tracking thru someone else's work. Everyone has a different means to an end. Doesn't mean 1 way is right or wrong, it just means it's different and much more time consuming to figure out someone else's crap. I suggest either:
A. Bring it to 1 shop who can do everything in house. Install, fab and dyno tuning.
B. Do it all yourself and don't involve anyone else in your means to an end.

The only thing about B is you don't have a dyno, so you will HAVE to take it somewhere eventually. Strapping down on a dyno is an expensive way to find out your car has issues that need to be resolved before you can tune. The OBD2 cars aren't the easiest things in the world to deal with.