My vote says simulate the minimum like you stated you want to. Fire can be a strange thing. Sometimes it can burn without alot of smoke depending on ventilation. With so many variables its hard to say what kind of damage would have been done by a particular fire.
+ doing the minimum allows you to add to it if its not to your liking. Easier to add stain than repaint.
The building is very cool..is the street made of gravel?
Good luck