The Banal was my first idea, and its really an iteration on the same techniques I used on my 'modern flatiron' scratch-build last Fall. The idea is simple: Print a window frame pattern onto clear transparency sheets (I have a laser printer fortunately, but I expect this would work with an ink-jet as well), adhere the transparency to a sheet of clear acrylic (shown with the blue protective film below) and then add various strips of styrene in different sizes to give the effect of a building.
Once the transparency is on the acrylic (of course, you need to make sure your printed window frames match up to your styrene sections), the styrene is glued onto the acrylic. Easy. I'm starting to believe that paper or thin card stock could easily (and more cheaply) replace the styrene.
I'm trying to overcome my natural bias against using paper or cardstock as I've seen so many interesting results from other modellers. While the signage and window details below are printed on transparency and decals, the actual exterior walls on the ground floor is just color printed paper ( okay, impossible to tell in the below photo, but you can see it better in the top photo).
I used acrylic sheets again for this building, but no transparency for windows. I did use some widow tinting material to get that dark, smoky look. The below photo shows the careful alignment of the exterior 'concrete' floor pieces, which are not only a part of the prototype, they cover yet more foam core 'floors' that separate each floor and act as mounting places for the LED bulbs (not lighting strips in this building, which gives it a different effect).
The photo below likely will not be the final position of these two buildings, but its a good place to temporarily position them until I get more progress on this area of the city.