Problem with trolley I thnk is you automatically worry about using too much water, then you reduce the pressure, use less water, but then the windows don't get good enough rinsing.
Cut loses, get a van mount ASAP,
Save all the lugging and filling of loads of barrels every night.
And get lightest pole and brush, VERY important, no disrespect to PF but generally the trolley package comes with a very poor pole.
Mr B