You don't need running water for printing. In fact, it's only needed when you wash prints, which can be done in batches. Limited space is a problem, but suffice to say that 4 20x25cm (or 8x10inch) trays will probably fit on top of a washing machine, like I do. Since the bathroom is right next to the darkroom, washing is not a problem at all. And I seriously doubt that you'll save any time using print drums. Tray processing is very easy and practically fool proof. Print drums can be a plus if you make color prints, but not so with BW. In fact, automated processors are ideal for color film development, where you'll have some obvious benefits.