i have added bevels to the main edges which catch the lighting nicely and help the silhouette  the poly count it still low whilst maintaining a good look, next step is UV and then texture!

tri count- 3,670

ive added more polys and fixed some more issues i also added bevels on the main building section on the leading edges to catch the highlights. i also added in a door with some detail which is hard to see from so far out..

tricount- 2,184

added the inward extrusions to enhance the silhouette
and optimized the building

optimized

ok i have uved this model
and decided from my good mentor Anthony (thank you again!)that the trims need to be baked to save the polycount
which is a very good idea!

now im going to spend the time to create a nice brick base 

changes made

i have made signifcant changes to the model to a good standard i think ive had the tri count is 2.8k still can get it down lower with verts and and edges that are not needed i.e backfaces
overall this model certainly has a lot of character once its approved im going to uv map and start texturing

as you can see ive got some changes which i need to make to get tha model matching the concept image.

i think the face on the concept image has more of a curve which will also needs to be edited.

initial model

here is the initial model which needs adjustments
its about 2k which is all good

here is the concept building i have chosen to model

ok i have added planes for the bottom window tiles which reduces the polygon count, however i have added trims (not finished yet) and they bump up the polygon count,

now i am thinking to maybe leave the window pieces as flat planes thus reducing the polygon count but that would mean i will have to create a  unique texture sheet just for the windows (originally i was going to have a tileable texture sheet for the window beams)
im not quite sure at the moment

with the windows modelled polygon count 19k
with the windows as planes = 14.2k

so far the tri count is 25k i think it can go down even further if the bottom tile window pieces are normal mapped
, now need to sort of some pieces and begin uv process then weld the the verts, more details like trims and doors can be modelled later right now i want to get this main piece uved asap