A trick to get more space in a bathroom darkroom is to use a wooden bar stool by the commode. Put a plank from the top of the water closet to the stool and use this for your trays. Use piled up photo mags on top of the water closet (you have lotsa mags, right?) to level the plank. Great space saving trick. The problem with the plank on the tub is that you end up looking like Quasimodo after working the trays a while. The other necessities are 1) an understanding roomie 2) the rolled up towel to block out the brightest light encountered in photography: the light coming under the darkroom door.
Have fun.

John (been there, done it) Mount Vernon, Virginia USA