I used to often have "hidden rooms dreams" when I lived in my parents' home, and still had them on and off after I moved out, but always of that house.
I had one of my own place the other night, which was a really impressive warping of topography, even for the dream world, given the size of my apartment.
It eventually morphed into an entirely new home, which was very very nice. High ceilings, lovely decor. And I recall it had a huge bathtub slash hottub ajoining an atrium with a little entertainment kitchen attached.
However, I was annoyed that I had to share the space with my neighbors, especially since their space was interconnected and intertwined with mine, and yet there were no doors, anywhere.
Very strange. I can't imagine what recent (or even not-so-recent) memories the dream-process was processing, so I have no idea where it came from or what it means.