If you are working with someone you could have someone jelly blade the vehicles after a pressure wash and foam cannon, then the other person could follow with a microfiber towel.
For team work also one person can handwax , the other follow and wipe to a shine.
When I want to quickly wash my car I just pressure wash it , use a foam canon, and jelly blade it. It always looks great (if you use a carwash &wax, one with wax in it you may not have to hand wax each car if they get washed monthly. (my opinion)
IF it is just you working I would take my time with drying a car really good afteryou wash it to avoid spots
With hard water there are cheap filters you can buy even at your local walmart that attach to any hose!