There are many motors, both electric and gasoline powered that one can attach to their bicycle to extend the range/increase speed. These might be viable for folks with less than perfect physical condition.
Does anyone have any experience with any of those?
I worked for UPS last year and had a trailer and a bike which I used to deliver my packages. I could haul up to 300 lbs over the hills on my route and still have some semblance of control. I would seriously consider a trailer as well as one of those gasoline powered motors to assist in long, steep ascents if they actually have the oomph to go. The gas ones appear to be fairly economical, you could cover a lot of territory with a two gallon gas can.