How much does this cost to the nearest dollar?

On The Go Spotless Portable Dual Bed Deionizer
Use the Dual Bed Standard Deionizer for all spotfree applications. No more hand drying or expensive 3rd party cleaning of your RV. This unit will produce 2 1/2 TIMES MORE WATER AND WILL REDUCE YOUR OPERATING COST BY APPROX. 50% compared to the mixed bed system. Dissolved solids are the culprit causing water spotting after rinsing your RV. The deionizer DI uses ion exchange technology that will remove all the solids from the water source resulting in mineral free water that leaves no spotting after rinsing a clean RV. The unit will produce approximately 505 gallons* of water good for 101 auto rinses or 17 class A RV rinses with a TDS of 250 at

Price is $400.00
Price: $400