Before moving into my first house last year, I decided to paint the garage floor to seal it. I used Rustoleum 2 Part Epoxy, gray in color, and proceeded to clean the surface and paint the floor.
Well, I a have problem with half of the garage floor, in that it is peeling. I believe the problem lies in the fact that I did each side of the garage separately, and really had to put the paint on THIN to get full coverage. The estimations on the instructions are way out of wack. I was under their estimations and still had trouble covering everything.
If I were to do this again, I recommending buying an extra gallon and really laying it on thick. After all, this is epoxy, not latex or oil paint. The thick side of my garage is in perfect shape. I've even dragged heavy metal objects across the floor, with only small scratches in the paint.