I have used zerorez for years. They always do an excellent job. I was quoted on the phone 97$. Which turned into 172. 1st of all my Living Room was considered extra large. So charged more. My living Room is not extra large by any means. Then it was extra to use as scrubber on my carpet. As long as I've been using zerorez I've never been told about a special scrubber.. I never actually saw this special scrubber used.
I do have to say the carpets look fantastic. I'm not sure I will use them again.