A sign of improved fortunes.
Anything that is next to us represents something close to the boundaries of our consciousness. For instance, if you live next to a mansion in a dream it might suggest that you already possess the resources to elevate your status and personal value. You just have to realize it.
Buildings and houses symbolizes your brain and how you think. Each individual room means a different part of you, your memories, and your emotions.
Can host many common dream symbols, but the building as a whole represents your inner psyche. Each room or floor can symbolize different emotions, memories and interpretations of meaningful events.