If there's anything I need to improve on it's my quality and efficiency in texturing.
Just 2 diffuse maps, finished at just under 2 hours.
I used a clouds then a sponge filter to create the metal base.
I used a noise filter to create the outer rim.
For the design on the window I defined a custom patterned from a box selection rotated 45 degrees to make a diamond, and used it to fill the space.
For the dirty version I just duplicated the clean version and edited it.
I erased part of the notice on the front and used the stroke layer style to give it a visible outline.
The graffiti is just a warped font with stroke and inner glow layer styles.
The general grunge was accomplished by fading a pattern via color burn in the layer styles.
The dirty window bits and some of the metal details were done by scribbling in the appropriate areas and making liberal use of the despeckle filter.
It doesn't seem like much progress for two hours of work, but I'm here to practice so that's kinda the point after all.