Is this an automated tunnel car wash, or a coin operated one? I worked at a non-automated car wash in high school. I'm having a hard time imagining how it would work without workers. During the winter, it was quite regular to have 1 inch of mud coating the entire floor of the car wash near the scrubbers. It was a lot of work to clean that stuff up after closing. I'd assume that your volume would be a lot slower, but still, there is going to be regular maintenance. It also wasn't that uncommon for people to claim the was damaged their car. I'm not sure how those claims were resolved. The car was is still there, 15 years later. I quit after getting held up at gun point, and it is in a pretty nice side of town. Certainly a low crime area.
Also, my experience was that the car wash tended to attract the near bottom of the food chain workers. Very low supervision and no required drug checks for employment also helped foster bad employees.
