There are some secrets to charity washes. If you think that the most effective way is to have girls in bikini's stand with signs, you are wrong. You need to get tickets presold, and have a definite timeline, say 8 am to 12 am. You also need to make sure that you have a minimum of 5 people at a time to help you. They will be using wash mits, drying cars and doing windows. Use DI water. It will make it far easier on you. Also do not let someone else use the gun.
Using these guidelines, we have raised over $2000 at a single carwash, in four hours.