[villagetinker]

I would suggest a firm like Docs Restorations. The typical hallway is going to be wider than the typical door and therefore framing would be involved as well as some drywall and matching wall finish. Then you will need the door frame and the door. Now depending on what you are after, there may be other options, a simple curtain with a pressure rod will provide privacy, an accordion door could be installed wall to wall possibly without the need for framing.