Well, as you can see, I've just be off gallivanting across the eastern seaboard with a little jaunt to the Boston area, which is both rife with vernacular apartment buildings and rich with very interesting, and elegant, examples as well.
Here we have the first entry in the series, with an example from Cambridge, Massachusetts (home of, well, you know what University). The Boston area is known especially for it's "Triple Deckers" aka a three-flat in our parlance. However, in this case it is a masonry building with grand pretensions, with yellow brick and limestone on the street elevation and red brick on the sides - none of our Chicago common brick here, one notices. It also sports a massive copper cornice and features copper bays on the opposite side from the courtyard.
Interestingly, I noticed few masonry three story apartment buildings, but many four and five story buildings - all in masonry, of course. As an aside, one can go much taller with wood frame construction, but that side note wasn't the case in the 19th Century with it's fire regulations (which often keep to much the same rules and regulations today). In this case we have five stories, with what appear to be many small flats within.
The building, this building in particular was alone, has similarities to buildings along the street as well as to similar sized buildings in central Boston as well. We also have rich beaux-arts detailing around the entry and in the previously mentioned cornice.
Nicely for the observer, the building to the right has been demolished, allowing a side view of the "courtyard" with it's bay window and fire escape. The windows of which have been nicely trimmed in limestone sills and heads.