They told me a 55 of RV is about $180.00 from where they get it from. For the season they said they use about 90 gallons, depending how busy your wash is and the outside temp. Its set up to purge 1 minute after the customer is done using the bay, the busier you are the less it will purge. One bad thing is you can't change the 1 minute time, if your really busy and your customers don't move in and out of the bay quick enough it could purge almost everytime. One other downside is you have to keep your trough warm so it won't freeze. The system purges from the boom out, it doesn't purge the entire line from the backroom out. They suggested a closed looped line run through your trough. They said to either hook it in to your floor heat or a small 6 gallon water heater with a recirc pump on a timer. The RV is considered safe by the FDA, but never asked regarding residue or paint damage. The good news is it will get rid of bucket washers and ice build up around the guns and brushes. Its a good option considering the rising water costs, I know in areas of MI water is suppose to rise by 40%. The system they sell is set up for 4 outputs, either 4 high pressure or 4 foam brush. They said its $100.00 for each additional output. For a 4 bay, high pressure and foam brush, it would be an additional $400.00. Oh, one other thing, if you use a rotary style switch, if the customer doesn't use the foam brush option, but rolls past it, it will still purge. If your saving a lot I guess its not that big of a deal.