you dont need prespray, there is enough crap in the carpet now. crystal defomer and a good acid rinse. and good luck. I have one the janatorial crew bonnet cleans the traffic areas nightly.i go in twice a year to flush the crap out, or try too. geeeeez. Total incompetence.
On a side note it is quite funny when they have a water damage, bubbles up to your knees. :shock: