Probably be easier to move house! If you go down the RO route you are always going to have a fair bit of waste water to deal with. Not really good for a soak-away or septic tank.
Re. pole for domestic I find a 22 foot pole ideal. There is the Phoenix or Gardiner range, suggest the full carbon version - e.g. slx22. These have a short collapsed length. My favorite brush currently is the Gardiner flocked sl standard splay, as it scrubs better than their other brushes IMO.