There are few instructables about residential space dividers.  These might permit folks to live more comfortably and economically. They could be temporary as well as permanent .
Could they rolll up to the ceiling ? Could they be flat against a permanent  wall until needed ? How important is acustic l privacy ?  Beauty ? 
Fire resistance and safety ?
If there are people who have thought about these issues or who have solved a space sharing problem, with some device or other, please post them. They are of no immediate concern to me or mine, but who knows in the future ?