I pay a monthly subscription fee of $30 at my local car wash to get unlimited exterior car washes. I wash the car everyday if I'm near the car wash and every other day regardless. I also keep glass cleaner and clean rags in my trunk organizer. The corner of the windows will always need to be cleaned daily because passengers tend to shut the door by grabbing onto the window. I do have a mobile car vac that I keep in my trunk also, and I usually just vacuum the floorboards before every shift. Dusting with a dust vac attachment and wiping down the seats is something I do once a week.