Sparklean charged $1.00 per sq.ft.
to clean and seal the grout on a porcelin floor. I paid around $200. and had to re-clean the floor twice to get off the excess film that was left by their method of cleaning. A foot high border was left along the wall surface of the rooms they cleaned.
Some of the film left on the floor had to be scraped off to get it re-moved.
The owner did return to view my complaints and spot cleaned a couple of spots.I had to clean up the rest of the mess.
Review about: Grout Cleaning.