Your kitchen uses 450 watts of lighting. How much does it cost if the lights are on for 8 hours a day, every day for a year if the local electric company charges 9 cents per kWh?
Most of the time, people use foam cannons to wash their vehicle with their pressure washer because a pressurized washer can knock dirt off better than a standard garden hose. However, if you enjoy having a car that is even cleaner than what a pressure washer can do, then you need a foam cannon.
Foam cannon is so much better than a foam gun. I have both, and I can tell you that much. The pressure from the washer produces much more foam than the one on a foam gun, plus you use less shampoo to do this. Also, the foam produced by the foam cannon, clings to the paint a lot longer than the one from the foam fun. This allows the foam soak up the dirt and grime a lot longer, thus even reducing the chance of scratching compare to foam gun's.