Two things I encountered when I went down to the cellar. 1.The street drains are above the level of the cellar floor, so I have to have a submersible pump in a container under the sink to pump the outflow up to the drain. 2. Ceiling height may be restricted; work out how much height you will need if you really mean to print up to 20 x 24; you may need to build an enlarger platform that can be lowered for those extra large prints. I have to use wide angle lenses which doesn't work quite so well, for me anyway.
Richard