Just to add what Russ has said, if's also done right, the results are really really good. Encap is the way to go on most commercial jobs. I have 12,000 sqft of commercial carpet to clean a week Saturday. Encap all the way.
Two men on a 17" rotary, and 1 man vacs, and pre-sprays. We should cover 1,500 -2000 sqft between us an hour. Steady away. Good money too. Dynamall on this beauty.