Like you matt I built my own trolly system with help from you , but I used the whale pumps with the jump charge batt pack .
After my pack died I been have loaned the surflow Backpack.
For £170 ( you can get it cheaper I know ) its a good bit of kitt , the pump , a Shurflow - has 4 speeds , it easy cleans 3-4 storys , come with its own battery inbuilt , and has a auto shut off pump so no wasted water . If you bought a pump and a varistream you are looking at £160 ish ( I just bought one ) so it's not bad money . Due to the big blue cap I can dump water into it from the cans quicker than it used to take me to change a barrel over a before .
Stick it on a sack barrow and it's the same thing , personally I wouldn't last a day with it on my back
on the first speed I can do a 4 bed detached house with 3/4 of the water in it ( about 15ltrs I think )
The Van - Its a Citroen Distpatch
pimped up with a second hand 300ltr REACH & WASH