Two things come to mind for me.Pre filter
Importance of the pre vac.
A couple things that I was never trained to use that I can't believe we ever went without. What are yours?
Tell me about this APO, is that an auto pump out?A reliable APO has made my cleaning so much easier. I have not had to stop and empty my recovery tank in over 5 years of daily cleaning - NEVER!
Inline vac filter with knee-high and stainless basket.
Dual wand truckmount cuts our working time almost in half (time is money)!