I have never used anything other than my DIY 50 liter trolley and a backpack.
The trolley has a mounted hose reel with 30 meters microbore.
It takes a lot less time changing containers than moving the van/ trailer.
I could easily run it as a van mount for the cost of another hose reel, but don't want the hassle of moving the van every couple of houses, or when someone wants to get in or out of their drive.
I too have very compact work, sometimes only have to move the car once in the day.
I ditched the van for a trailer, I can carry all my water, and have a ramp to wheel the trolley on and off.
Having my Mrs at home means that she can fill all the containers for the next days work, I just chuck the empty ones off, and reload full ones for the next day.