Send a PM to Bachata here on DR1. He can fiz you up with a reliable driver who will pick you up at the airport and deliver you safely to your destination on the North Coast.
the fare for a gang that size will be in the "neighborhood" of $150...I say "neighborhood" because a larger mini-van will be necessary...
Just tell JJ (Bachata) what it is you need and he will arrange it for you, I am sure. He has done this many times.
Cordially
HB