

You’re right, there are not many hills here. Only 1 small one I had to climb. I do think that with low enough gears and enough time, hills won’t be much of a problem.
You could also do the hill in multiple trips, temporarily leaving one of the trailers behind.
It’s actually not bad at corners. You’d probably be fine cycling maybe a metre further out than usual.
You could probably move a similar amount on just one large trailer, which might be easier to manoeuvre round a city. Bikes at work has some cool examples: