if it wasn't for the fact that I hate mice and rats and snakes, I could do that kind of work.
Driving by them and you can envision the beauty from back in the day is kind of sad. But yes all you mentioned is recycle-able, if it hasn't been stolen and sold for scrap...
I wouldn’t worry to much about snakes in a urban setting, I am sure there are snakes in cities, but most would be in parks.
I was walking one day on a road and heard something in the weeds, it was a black snake and it hurried away quickly.
Most snakes would try to avoid humans.
Now rats and mice are another story.
But even rats and mice will try to avoid humans , unless they have rabies.
I would worry about any infectious diseases from rat crap and mice crap.
By the way ?
The best way a contractor showed me how to tear down old walls and ceilings with the old wood slats and plaster ?
Instead of beating and hacking the walls or ceilings with a hammer, is to put a hole in a wall or ceiling then take a 2 x 4 and pull on the wood slats.
Much better than taking forever with a hammer or slege hammer.