Hi
Im fairly new to WFP-2 years at it now .I think your missing the water filtering at home bit unless the tap TDS is very low in the areas you wish to clean. I need to pre-filter water before going through di to polish water down to 00 tds . I get through maybe 15 houses in a day depending on size nd have found 5 25l containers is okay for shorter winter days , you would need a couple more for those longer summer days .I thought about fixed tank in my vivaro but use it for other things so like to be flexible. Lifting trolly and containers in and out doesnt really bother me ,Im a fit 53 and see it as good exercise.I did find it a bit of a problem getting back late and needing to fill containers ready for next day with slow filling RO, Bought a booster pump which speeded pure water production up by a third.Dunno how far Im going with my business but some on here make vast quantaties of water very quickly with right resources but equals more cash outlay.