To me Grosse Point MI would be a sound guess if there weren't two separate buildings in the background: the windows are on different level. Therefore the floors are on different levels, too. I have never seen a large private residence that would have been deliberately designed so akwardly. Therefore, there must be two separate plots. Townhouses built wall to wall to each other. Furthermore, there would seem to be a passageway between the buildings, leading to a backyard. Therefore, a city building. - What do you think?
A city building is the best guess I agree with you, especially if a courtyard is present..
As somebody already mentioned, Detroit always had land area to spread out as it grew. Places like New York City were relatively landlocked, so they built UPWARDLY and DENSELY as they grew .. you'll get places that look like that Sloan-Gould property. Two residences BUT effectively THREE buildings each slightly different.
Then you have this thing .. the Henry Frick House on Fifth Avenue across from Central Park.
Henry Clay Frick House - Wikipedia, the free encyclopedia
Frick House has got a "driveway" in front of it, its limestone construction with Italian design, looks like three different buildings though its not, and its gigantic even though it was built as a single family home . Upon close inspection, it is NOT the brochure building though .. and its one of a hundred similar buildings sprinkled around NYC.
Now if you just drive the "Google Map Man" around the corner on 70th Street (the street to the right (South) of Frick House), you get this "similar" but also incorrect set of three buildings ..ALL different single family homes. The Upper East side is full of these plus the commercial buildings.
And we havent looked yet in Washington, or Philadelphia, or Chicago, etc. Or even buildings that may have been torn down since 1969. So our challenge is obvious unless somebody finds the information we need.
All the best in the search .. I will be watching and helping if I find anything new .