That looks so full of promise already!
is the wooden boarding balsa wood hacked up a bit with a scalpel?
Yip.....and I've used a sharp pencil just to draw some lines on it, to make it look more worn.
Beautiful work. I live in awe of your skill. 
What size brick plasticard have you used for the exterior? I've been unsatisfied with the last couple I've tried but that looks spot on.
Thanks Cypher!
It's 7mm stuff mate......
http://www.antenocitisworkshop.com/slaters-7mm-paving-grey.htmlThat's brilliant. Will you be doing illuminated signage? 
No lights will be harmed in the making of this building!
Thanks Mark!
I've gotten a little bit further with this and I've also received a small care package from my client to use in dressing the base....a dumpster and a few trash cans.

I've also made him up a wee extra to go with this....

Thanks again guys!