If you can find one an Omega D2 will handle your 35mm, 120 and up to 4x5. It has a single column. I have used it with a condenser, cold light and now for a number of years an Aristo VCL4500 light source (no longer produced). That light allows dialing in contrast levels similar to what jp498 mentioned but is not a color head so you would be limited to B&W. With a condenser or cold light you can use filters to vary contrast. Variable contrast papers are more economical and available than keeping a supply of graded papers.

As for size, if you have a room that can be made light tight you would only need running water to wash film and prints. My first darkroom had no running water so I washed film and prints in the kitchen. Once they are developed and fixed light or darkness are not an issue.

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