[l2ridehd]

Minimum width for a toilet is 24 inches, 30 is better. Yes you can tile the floor and it will drain fine. They use a rubber membrane to form the shower stall floor and and can custom fit it to any size you want. Then put a concrete/grout like mix over it, then tile. My master bath here in VA has a shower that is built on an angle wall and is like 3 feet wide at one end, 6 feet long on one side and 4 feet long on the other. The door is actually in the angle space. The shower pan was custom made right in that odd shape using the thick rubber membrane

As for shower doors, they come standard 24, 28, 32 and 36 inches, but again custom glass can make them any size you need. As an example for the shower above, the door is 31.5 inches wide. Wouldn't go much less then 28 inches for comfort reasons. Just have them build it any shape that fits your space, call a glass company and they will build the shower glass walls and door any size/shape required. It really is not that expensive to do it that way.