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.
Anything that "anyone can do" is going to explode at some point.