I had the night club in oasis go unavailable for me. Took me ages to figure out what was wrong!
Each community lot needs a certain number of items for it to count. If the requirements aren't met, the lot goes unavailable. I realized when I went into edit mode that some sim had walked off with the guitar and violin that are on those lots. I had to put a musical instrument down before it went back to being available. A little rearranging, lets see them try and steal the piano! Silly klepto sims!