There is a little bit of everything. Flat ground, mountains, dunes, washouts, sand hills/berms, etc. One hunt I had to stalk/run in a washout for about 600 yards is all and the last time I went I just about killed the guy I was helping. We were walking through a dune area in soft sand for a day and a half trying to kill the grand daddy and he was just plain wore out.
He went down there with the impression that he was going to shoot from the road. On the second day of a two day hunt he shot a respectable bull with a broken horn that the taxidermist was able to fix, but we probably would have hunted differently if he would have been in better shape.
I guess that just because it looks flat, you shouldn't anticipate that it is going to be easy walking. If you friend only has a problem with the vertical stuff and is in relatively decent shape, you shouldn't have too much trouble. Get the best glass you can afford!!!
