My house was built in 1995 and has that lovely, 12" white porcelain tile that just makes you want to cringe and cry over the ugliness. I have no plans to replace the floor any time soon (75% of the house is tile) as it's just my starter home. All the grout had turned a wonderful shade of dark charcoal (originally was off white according to the tile in the closets) and the tile in the kitchen looked like my 4 dogs held a bachelor's party there. No amount of cleaning, steaming, scrubbing had helped before.
So after reading reviews, I decided to give Dan a try. After all, how much worse could it look?!? Holy sugar plum (I said the adult version out loud to Dan), his cleaning supplies and magic scrubber machine made the floors look really good. The kitchen tiles were white again, and with the new grout paint and seal?!?! I was floored, I kept staring at it and saying Holy S*** (which made Dan laugh a bit).
If you need your tile cleaned and grout resealed, call Dan. His prices are very reasonable and he gets the job done very efficiently and as quickly as can be expected.