We wash around the pillars and outer walls immediately after the sweeper goes through. By doing this the ground is pretty dry before the scrubber does it's thing. The less water it needs to pickup the better. I run both machines and the helper does the washing and loading of the trailers. Trust me I'm all about power washing but these machines make our lives so much easier.
I am a sponsor of the Houston event but unfortunately not able to attend as something came up. I'll have some giveaways there. Have fun and learn lots!