The model is inspired by a building in munich directly across the main station. It is still existent although it has been massively simplified.
Today it looks like any other building. It was built around 1880 and the model reflects the state at about 1900.

The building comes in a couple of parts:
1) OB01Poly - The outer walls of the building; if you don't plan to use the patio, this prefab would be enough.
2) OB01PolyBoardwalk - The board balk around the building
3) OB01PolyHandrail - The hand rail for the stairs; can be ommitted.
4) OB01PolyPatio - the inside walls forming the patio.
5) OB01PolyPatioFloor - the floor for the inside patio; only required when the patio is used.
6) OB01PolyPatioHandRail - the hand rail for the stairs in the patio.
7) OB01PolyPatioStairs - the stairs in the patio. Can be used alone or can be combined with HandRail and Add variants.
8) OB01PolyPatioStairsAdd - additions to the the stairs in the patio. Leave these away when you're under tri pressure.
9) OB01PolyStairs - The stairs.
10) OB01PolyStairsAdd - additions to the the stairs at the outer walls. Leave these away when you're under tri pressure.

If you like to use the additional prefabs, just place them at the same location as the main prefab.
(If you require the inside of the building to be modelled in detail, let me know, I'll see what I can do.)

There are two combined prefabs that can be used as is:

OB01PolyFull: all parts of the model combined; this uses the most tris (90,668 verts, 54,384 tris)
OB01PolyMin: minimal parts required; this uses as less tris as possible (37,546 verts, 21,948 tris)

The meshes are built from submeshes separated by material, so the materials can easily be changed.

Current number of verts and tris:
1) OB01Poly 37,058 21,692
2) OB01PolyBoardwalk 464 312
3) OB01PolyHandrail 2,424 1,400
4) OB01PolyPatio 24,942 14,610
5) OB01PolyPatioFloor 4 2
6) OB01PolyPatioHandRail 2,528 1,456
7) OB01PolyPatioStairs 488 256
8) OB01PolyPatioStairsAdd 11,136 7,200
9) OB01PolyStairs 488 256
10) OB01PolyStairsAdd 11,136 7,200

The package contains 5 textures (for the windows and doors), 5 normal maps and 17 materials.