Of course, it's true what you say...
Well, for that is better somebody who actually knows about Teheran as you say... maybe a picture of a real building there in the city? and if is not made with the style that you required, a bit of photoshop for make it more... suitable? Actually about Iran I don't know very much, but yet i'll try to tell you anything I can find.
Remember, where I can give my best support is when you made the Venezuelan civ, although I'll try to help you with all others you want to make!