I made a DIY trolley,.. but even in its second incarnation, stripped down and as lightweight as possible, dragging it in and out of the van and lugging barrels of water (never mind the work & time filling them!) was hard work! I had about 15 mtrs of hose on mine, so for most houses I didn't have to move it much to get all the way round, something I'd defo recommend to all new trolley users.
For my round the new van mount setup is much better, and saves me a lot of effort each day,.. I just have a backpack for the occasional awkward job.
I'm not knocking trolleys though,.. it all depends on what suits YOUR round,.. and every round is different