I have never found a good place like that to wash my car. However, if you have ESSO Tiger car, you can wash your car free based on every 399 points.
Normally I wash my car by this way. If you don't save so many points, you also can spend ca. 5 or 6 dollars to wash your car after rebating by your card.
It is an inside washing by machines. You don't need to pay tips.