Window cleaning is such a niche service that most people don't even know there's a difference between cleaning your windows the normal way and having them cleaned the right way. Two things make a big difference. First is using deionized water, which is pure H2O, so there's nothing left behind when the water dries. Second is actually cleaning the frames and the sills, not just the glass. That's where lots of dirt and much collects, so every time it rains or the sprinklers hit, that stuff can splash right back onto the window. So the way we do it, the windows get cleaner in the first place and stay cleaner for longer.