What are people's approaches to washing cars? It seems the options are:

• Wash at home on grass (not an option for us)
• Wash at home on the driveway (technically allowed where I am, but pollutes the rivers, although may be OK if you can find an eco wash and wax product?)
• Go to an auto car wash (not too expensive, but likely to scratch up your car)
• Pay someone for a hand wash (costs hundreds)

I just washed our car on the driveway, and tried to minimise run-off going into storm water, but it didn't work that well. Have found this product, but no idea if it's any good, or greenwashing.

Any other ideas?