razmuz,
I used to walk to my deer stands, and have been known to drag a deer several miles back to the truck. After an auto/motorcycle collision years ago (I was on the motorcycle), my normal gait now tends to have me walk in large circles :-) .
I got an ATV several years ago. The first one was a 2WD. It took me anywhere I wanted to go, but I found that, on some occasions, it was difficult hauling a deer out of rough terrain. So, I traded it for a 4WD. The 4WD is less maneuverable, but it still gets me any where I want to go and hauls a load better.
The only thing I found about an atv that is not used regularly is that the fuel needs to be treated with a stabilizer to keep from gumming up the jets during long periods of non-use.
For a guy your size, anyone of 400cc or better should be plenty to get you around. With as little use as you plan, and it is stored indoors, an atv should last you for as long as you need it,
You might, however, find that you will ride it more than you think you will.
Best of luck with your choice.
TnNuc