I've just bought a gelding for myself and my wife is very actively searching for her horse.
We have a 3 stall barn with tack room that we're fixing up. We plan to use the 2 box stalls that open directly onto a pasture. The horses would be able to walk right out. I've seen lots of barns with a small pipe corral outside each stall. Is that necessary? Obviously, we'll separate the horses when feeding. I just wondered how territorial horses would be about their stalls since they both will be open.
The barn pasture is on a gently sloping hill with lots of flat spots. They'll like it. They'll be in neighing range of several other horses. There is one corner that has been seriously eroded and I plan to move the fence in so that the horses won't walk there. I fell down with the little ravines hidden in the tall grass.
There is one somewhat eroded spot right by the stall doors. It's flat where the horses come out and then slopes at the edge of the barn. My wife made a 4' high wall out of some cinder blocks we had laying around. I'm not so sure this is a good idea. Even if I stake them in place with lots of rebar I don't like the idea of rebar & cinder blacks in a horse pasture. It seems like they'd risk scraping themselves. I had been thinking of a run or two of 3 rail wood fence there. That would keep them from walking through that spot. It will get a lot of attention from them anyways. Water flows through there so the grass is very green.