When I did a car wash for a sports group, We went to a local grocery store (or gas station).They provided the water for free. We got a bunch of hoses (make sure to have an extension to hook all hoses into one facet), buckets, and cloths. We would have some kids by the road(with adults) with signs and set up two lanes for washing. We would split the kids in half to the lanes. Adults would take the money and check the cars before they left. Once in a while change the kids around to do different areas. We charged $5 a car and made just under $500 in three hours.
Our Girls Softball league does one every year as a fundraiser. They charge $5 a car. Just last year they started pre selling tickets. They said that worked much better. Plus you got people who bought tickets who did not even get their car washed. I believe they said they gave each kid 10 tickets to sell and had them just turn in the ones they did not sell.
Also, in Colorado when we did it, the car wash had to be free but we accepted donations. I can't remember the legal reason but that's how everyone has to do it.
Go to a nice car wash and see how they have an assembly line. Some one drives the cars through slowly. A couple kids do a first rinse. Car moves forward. Couple kids wash. Car moves forward. Couple kids rinse.
The other way we used to do it was to have teams that work one team per car.
Either way, you need a couple sources of water and lots of buckets.
Also don't do it at the school if you live in an area with lots of clay. (IE Denver foothills) Clay soaks up the water and expands and can cause foundation damage and shifting.
I know if you do it at a WalMart, often the manager will match what you madefor your group but you really need call in advance for that. Otherwise in high school the cheerleaders did, too long ago to remember!
We can't here in Colorado, still in a drought and under water restrictions!
