Dont forget guys unless you are there to specifically attempt to remove a stain or stains, you cant afford to spend a lot of time or solutions on them. In the course of general carpt cleaning of course it is right that you should treat a stain with the appropriatte solution, but if it doesnt come out, dont go at it again and again. Only do that if the stain is the primary reason for your visit. The customer will understand if you qualify the chances of removal prior to cleaning.
Dave.