I will try to post some pics of my new barn. Not as big as you are wanting, but is has a VERY multi-purpose room in it. The dimensions on the room are roughly 26'X14'. We did a small 3/4 bath and a kitchenette. Hopefully it will have a Murphy bed. We bought inexpensive all weather wicker from Big Lots to furnisn it, so it will be easy to move around if someone needs to stay in it.
The room is supposed to be my office, trophy room, dress harness storage, guest house, break room, etc......
LOVE the barn!! It is 84'X 40', with a 14' shed, so the entire covered part is 54' wide.
I have 6 box stalls, and 9 standing stalls. The center aisle is16', and there is a 12' cross aisle. I need an area to harness multiple horses, so we used the area next to the office for that, which makes it 24'X 26'. This area is also the wash area.
It is not a fancy place, but I worked in a 34'X 36' barn with only 2 stalls, and a 10' aisle for 10 years.
I will hopefully do a "barn warming" reveal thread later, so I will save some other details for that, and not hijack your thread!