I would say go tandem axle if its your only trailer. Its nice to be able to get a few yards mulch, 15 or so plants and mowers on at the same time for a daily route. No need to make a seperate run to do a job when you're already there to mow. If your goal is to have brakes they should be on every wheel on every trailer anyhow.
I've never been skydiving, but I have zoomed-in on Google Earth really fast.