So I recently I have to park my car outside at work. Before I was able to park in a roofed structure, and in the garage at home. Here in SoCal, the car only gets dusty/dirty from being outside every day, but washing every week is just overkill.
I'm into detailing as well, and discovered the waterless wash, namely the Ultima Waterless Wash Plus. There are other brands too, but I read many good reviews on Ultima, so I went with it. Tried it today, and works very well. My car has a week's worth of dust from sitting outside (you can't see the dust unless you touch it). I diluted per the instruction, used a spray bottle, wiped with 8 fold microfiber towel in straight lines, and the car returned to the just washed look. In my case, the car is waxed and clay barred, so the paint is already very smooth to start with.
Overall, I really like this product. Economical, Fast, and perfect for my need, which is maintaining or light cleaning the car in between washes. I just want to share with those who didn't know about waterless wash products like me until now.
