We just built a ramp for my father who broke his neck last fall. His is pretty basic - straight up, long enough to make it not a ridiculous incline.

We also needed to put in a handicapped shower, and a strong rail by the toilet, but other than that he gets around pretty well in the house. His chair bangs up the wall a bit.

Incidentally, my brothers and I are working hard to get him a deer this year. He has had a couple close opportunities, but no luck yet. Hopefully he'll get one this weekend.