i started on a trolley but found it difficult changing barrels and annoying priming the pump, i think its much easier out of a van mount, no running out of water or changing barrels, and its easier pulling out a hose and reeling it in i find. I would still use a trolley, keeping it in the back for some houses, but it does get annoying changing the barrels as they run out quick. Both would be good if you could have a trolley in the back with a van mount it would be much quicker and easier to fill up the trolley again.