I go to the coin operated car washes. Wheels first, then from the top down. I bring my own soap, chennile wash mit, OXO feather tip brushes (one for wheels, one for top), and I use microfiber fiber waffle weave towels to dry the car. Basically I'm paying for water because I don't use the brush that's usually lying on the floor full of rocks. I can do it in five minutes and its costs $3.00 in quaters
The high pressure is good for the top, as I only rinse it mostly. But if it gets soiled(birds) I spray in Ragg Topp clenaser, lather it up with the OXO brush and rinse. Blot dry with waffle weave towels and later on I'll reapply the Ragg Topp protectant in an indoor parking garage. You know its working well when the water beads after rinsing.