Adding a Powder Room

If you're refering to 801 West End Avenue, the agent told me that it's not possible to put a toilet next to the shaving closet!

That is probably the shaving closet, yes, but in general what is required? I imagine that a sink is easier to do than flushing solid waste. Got any plumbers or contractors out there?

Installing a toilet or powder room is not technically difficult. However, many coops (and even condos) will not let you add or expand a bathroom (or kitchen) unless are installed directly over an existing kitchen or bath. So if your downstairs neighbor doesn't have a bathroom, powder room, or kitchen below the area where you want to install a power room...you often won't be allowed to do it.