I don’t see how a driver could makes any money for $100 round trip. They arrive at the airport early and wait around for to get through customs and immigration, provide beverages and pay the expensive fuel costs. I totally understand trying to get a good deal because it is an expensive vacation but service providers must make a living. You can find airport transportation for as little as $20 - $30 one way, it’s shared. Even Juta Tour charges $100 pp round trip. I think additional persons are $15-$25 each. Like has been said don’t forget to tip!