Good points! Yeah I figured it would be more expensive, but I don't want to loose potential clients because I don't have windows..
Maintenance- Stone would be a good idea, but I probably wont do that until I have most of the barn debt payed off. So for right now just grass, and I would whipper snip it instead of trying to mow it. The space is about 6 feet from each "wing".
First off-you cannot please everyone all the time. The key is to make it as nice as possible at an affordable price for everyone, IMO. Windows are not the be all end all. Yes, they are nice, but, at least for me there are so many other factors I look at when choosing a place to board. Above all is the reputation and the care. Then we go to ammenities. Window is WAY down the list, after indoor (with GOOD footing, discipline appropriate, and well maintained, I might add), tack room -NOT lockers, since I have a custom tack trunk, need a place to put it, and frankly cannot stand barns that have trunks and crap in the aisles, just waiting for a horse to crash into them......an accident waiting to happen, as well as messy looking IMO. Trailer parking, don'T nickel and dime me for blanketing, etc. A dressage arena is nice, and a good size, but just make sure you do not limit your clientele, unless that is what you want. I will also say that personally I would never board in a place that is a "dressage" barn. I drive over an hour now to see my guy, so that I can have a place I can comfortable ride western and do my reining. My area is FULL of dressage barns, with a few H/J thrown in, none of which I felt welcome in with a western saddle.
So, I don;t know what your area is like and what is popular there, but make sure you have the market to support what you are building.......
THere is, IMO, no reason to up your cost SO much with all of these extra wings, unless of course $$ is no object, now, or in the future, for maintenance of the extra roof area, doors needed, etc.