Light leaks are a problem with an improvised darkroom. Most fabric stores sell a material called "blackout" cloth. Its white so could look like a regular curtain; but functions very effectively in blocking light.

Another suggestion ( mentioned earlier), BTZS tubes for print development. I constructed 3 tubes out of 3" grey electrical conduit pipe (total cost, around $60). I used male/female screw connectors for connecting the print & chemical sections. It may look like a plumber's version of Davis' BTZS tubes, but the screw connectors functions much better than a single connector. I half-fill a plastic closet bin with water at proper temperature, set my chemical bottles in it. Once chemicals' temperature adjusts, pour chemicals into smaller sections of tubes & begin processing by floating/spinning conected tubes in bin. Less chemical usage, less mess & small footprint.