OOO I hope I didn't come off as a fobit.....
I have a bodyguard client that I wear plaincothes with. I often am the only one, and carry in a shoulder holster when driving. BUT, I also have to stay with him when we reach our destination, so I also carry IWB at 3 o'clock. I do that because I KNOW that is where I will go to when out of the car.Side note 1: Crossdraw can be very useful if your primary duties involve staying with the car, and the only reason you are getting out of the car is to defend the principal. It is easy to access the gun and already has it pointing in the correct direction if you're a righty.