My favorites were the ones I'd see old ladies riding in town in the 90's. They were tricycles: one tire in front, and two in the back with a large basket between them. They'd go buy groceries and come back without straining themselves with the bags.
they're still available, in electric even these days! Though tbh you'll also get by perfectly fine with a normal bike that has a basket on the back, yeah you'll have to lift it up and it'll be a little bit wiggly with the weight up high, but it's absolutely fine if you're in normal health.
I've always wanted one of these but lord knows I'd never get my money's worth out of it. I'm either shopping for stuff I can carry or enough stuff to necessitate a vehicle
Yes... I'd love to make one myself. I have an idea for one with swappable wheels: small wheels which don't stick up above the trailer bed (for carrying wide things), and large wheels for a less bumpy journey.
The hand cart which I have at the front is great for carrying large/wide things, but the wheels can't handle cattle grids or rabbit holes...
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.
Does a trailer add a bit of stability? My better half started having balance problems in the last few years and no longer feels confident riding a bike outdoors. He is also taking blood thinners, so his cardiologist encouraged him to stay on the home trainer. As an ex bike racer, he isn't enthusiastic about riding a shopper trike or 3 wheeled recumbent either. (A bit of machismo there!) But maybe a trailer would salve his ego.