Anything that "anyone can do" is going to explode at some point.
keep assets instead of cash and you'll be a genius
The "somewhat specialized" knowledge can be explicited as four main things:
1) years (and I mean years) of experience in the field (to be able to quickly assess the non-evident potentialities of a building)
2) knowing a few good, tested, reliable technicians such as architects/engineers (to be able to get a valid project leveraging on these potentialities)
3) knowing (more than) a few good tested, reliable, capable firms (masons/carpenters/plumbers/electricians/painters/etc.) to actually execute the restoration
4) time to be dedicated to managing the project
If you think that - even if you actually happen to find a "gem" - that you can make money hiring people you find on the internet or on the yellow pages, or that the people involved will manage to do a good work at a fair price by themselves, you won't go very far.
And it is not like you can find such disasters easily, nor that you can easily be able to make them into fixers, without years of previous experience.
The whole approach, "everyone is scared but you know ..." is based on the assumption that you know more than anyone else (possibly including many people dealing with this kind of stuff for decades), I doubt that anyone can learn what is needed in this field overnight, by reading a book, and should it be possible, everyone woild do it, not just you.