One of my favorite mansions is probably one of the quirkiest in Detroit as well... the 22,000 sq. ft. Lawrence Fisher Mansion... AKA Hare Krishna Center. Ironically for such a large house, it had only 2 bedrooms.
It was designed by my favorite Detroit Architect C. Howard Crane [[for obvious reasons). And like Crane's downtown movie palaces, it has an exotic mix of architecture, and would be right at home in a Florida setting.
Here's a video clip I just found on how the new owners [[Ford, Reuther) helped restore not only one of Detroit's great homes, but also helped revive a neighborhood.... although I'm not sure how the older residential areas around it are doing today...
http://youtu.be/ab39SrarSB8