Years ago, when I had my own place (well, the bank's place actually, as they told me in court) I did a bathroom / darkroom conversion. Used the bath (obviously !) as support for workbench, which was 8' x 4' of marine ply, varnished, hinged along the wall edge of the bath, with battens for support. Enlarger at left end, with elongated column fixing to ceiling bracket (I could do 20 x 24 without rotating the head), dev dishes reading to the right, entire bath turned into print washer with a syphon in the plug hole and mixer tap on low at 15˚ Celsius.
Unfortunately, I had rigged up unofficial wiring to power everything (all perfectly safe - sockets just below ceiling height, circuit breakers, the lot) and the Health and Safety Nazis found out about it and ripped out the wiring. Since then, I have lived in rented accommodation with no bathroom (just a shower, which ain't the same), so no darkroom. Maybe when I get dumped into a retirement home I can fix up something there . . .