I used a 9x13 shed at my old house as my darkroom. I did install an old kitchen sink and faucet and plumbed the cold water to the outside with a hose bib on the end. Just had to connect a hose from the house to the bib and had cold water for print washing. The drain was plumbed out to the grass. Also ended up installing a small AC unit in one of the windows because the New Mexico summers get really hot. It was a pain to get up and running but when I did, it work like a charm.