@Steve-Miller said:
The office building is actually on the back of the house and appears to be an addition done in the 1970’s.
That's what caught my eye in the listing. I know that stretch of Wheeling Road well, as itis just a few blocks north of my Mom's townhome/condo subdivision. I was like "where is there an office building on that street?"
@Steve-Miller said:
Looking at the baseboard heat, (is it electric?)
Possibly, but more likely hot water powered by a gas boiler. We had a similar arrangement (zoned hot water baseboard and vaulted ceilings in an open floor plan with lots of windows) in Door County and it was remarkably comfortable. That house was built in 1991 and had good insulation and quality windows.
That the water source is “Lake Michigan”?
Prospect Heights is between Mount Prospect and Arlington Heights, a bit more rural than typical suburban and sort of an outlier in the area. It doesn't have a "downtown" like the other 'burbs that are on the Metra commuter train line. A PH station was added when commuter service was initiated on a RR line that goes through the east side of the town. That wasn't that long ago.
As you noted, homes built in the 1930s, most of them on half acre or larger lots. When we moved here in 1980 PH didn't have its own police or fire departments. They got police and fire service from surrounding towns and the Cook County sheriff's dept.
https://www.prospect-heights.il.us/130/History-of-City
Early homes in Prospect Heights and even our town were on wells (and septic) but later construction included municipal water and sewers. The municipal water was not from Lake Michigan; each town managed its own wells. Eventually the towns connected to the Lake Michigan system. Not sure exactly when, but our 1960 house had a water softener that was switched off because by the time we bought it in 1980 we were on Lake Michigan water. My Mom's 1980s PH condo that she bought in 1995 didn't have Lake Michigan water until a few years after she moved in.