6 Grand!!! You could easily get a decent set up for under £1000, why waste your money?
Ah, I thought he meant VAN and system. Not just a system.
LOL! No, don't spend £6K on a system. It's just a tank, a pump, a battery, and something to control the rate your pump pumps water out. Add to this a method to purify your water, hose, a reel, and a pole, and you're ready to go.
It's very simple really; groundy is spot on.