A number of years ago, I was a part-time driver for some of the girls.
They paid me $30 - $50 depending on where the call was and how long I had to wait. I didn't make alot of money, but each of them would give me some freebies when time permitted - BJs mostly, but some of the girls would let me fuck them because I only lasted 2 minutes and it was a quick and easy way to thank me.
The biggest problem with being a driver is finding a place to park and wait while the girl sees the client. Sometimes, I had to drive 15 minutes away from the call to find parking that was free. Drivers usually stay in the area until they get the OK from the girl that everything is safe and they don't need to come upstairs to help the girl with a bad client. Once you get the OK, you can go somewhere and park until she is finished and needs to be picked up.
I have dinner with some Asian girls once a month and I always tell them that if they need a ride for outcalls, I will try my best to help them out. These girls are my friends, so I told them 'No Charge and no reward needed.'