To get straight to the point, this jet nozzle high-pressure hose-end ... with a cleaning solution that attaches to the hose for extra cleaning power. I suspect that wouldn't be necessary if ...

Luckily, this Melnor hose nozzle is very affordable ... a setting like a full shower could also work. Power-washing a deck: Use a jet spray with any of the nozzles above except the rain wand.