I worked out of a half bath darkroom while in an apartment (I guess that was darkroom #3 of 6 or 7, depending on how you count them.) I had a set of boards anchored to the wall on either side of the toilet, in an area that was about 3' wide, to act as supports for temporary shelves that I made to support a cascade of trays, with an enalarger basebard sized top shelf.

The enlarger sat on the top shelf, and then after the paper was exposed, it was slipped under the top shelf into the developer tray, then sideways into the stop tray that lived on the same shelf as the dev.

Then down a shef to the fix tray, and then sit in the HCA tray for a while until it was time for fix 2, if printing FB.

The fourth shelf held a larger wash tray (I think it was 16x20, and the other trays were all 8x10) It was fitted with an automatic tray syphon that drained though a hole cut in the shelf to a little trough screwed under that shelf to deposit the drain water into the toilet.

On the 'dry' side, I made a shelf on struts that sat over the basin. There was a hole cut in the back of the shelf to allow me to control the water from the faucet, which usually after the chems were mixed, was used to feed a hose that fed into the wash tray syphon.

So yes, I have lived though your pain. The layout I describe above was what I cam up with after working in an impromptu half bath darkroom setup, and swearing that there had to be a better way.