old pole,1 fan jet, electrical tape , pole hose and connectors and pump up sprayer = job done
i use an extel hybid pole lol £100+ , for this purpose only as it heavy and useless for window cleaning, compared to an SLX
BIGGEST WATE OF MONEY = CHEAP POLES for window cleaning.
get an harris pole from b&q and use some pole house connected to a fan jet and a pump sprayer, i use an angle adaptor on the end of the pole that is taped up in position ,as i use this pole for high internal clean scrimming.