@Mad Mike the simulation of hired drivers is pretty simplistic as far as I can tell. Some of them have a bit of experience, but all charge roughly the same. I typically hire ones with a bit more skill at first and micromanage the first five garages, then after that I just set them to balanced and forget about them. I tend to place garages at the extreme edges of the world (I have all the dlc so it's a rather large map) and work my way in from there. Cheap starter trucks until im earning millions, then trailers and mid range trucks from that point on