My house is about 15 years old and the grout in the kitchen was in really bad shape. I didn't really realize till I replaced a few tiles and had to regrout the area. I bought a small bottle of grout paint from Home Depot for twelve dollars and change, figured it was worth a shot. Did it over the course of a week or so, only about an hour a day max. It came out great, and supposedly seals it also, we'll see how long it lasts. If i get a few years out of it I'll be happy. It looks awesome though!