'stonemason' provides the ultimate in urban textures and his stuff can be found at daz and some great stuff at dexsoft all nicely priced.
Use Deleds editor to construct most of your city.
If you make your scenery buildings as boxes the x file size is about 2kbs. Do the maths i.e. one hundred buildings to surround your city = about 200kbs compared to the existing urban buildings in fpsc which are each megabytes.
Export as x file and make a new fpe file
use transparency to create empty deserted look
Use signs program to create walls from other textures, brick, alley,fence etc.
I used deled to create a whole city with battle tanks for darkbasic
http://forum.thegamecreators.com/?m=forum_view&t=161151&b=10
I'm working on the same idea now for fpsc9 one big ruined city with lots of gameplay.
heres an example of how textures will look - black space being transparent
mpc