Otherwise frozen pipes may happen.

The pipes have to be dewinterized so I would have a plumbing professional there prior and when the water gets turned back on just in case.

I am, however, a creative thinker that likes to exhaust all avenues before moving on!

Often times older properties come with aluminum wiring or lead pipes. 

If I was the tenant that got damage from another tenant's water heater, I would expect him to pay the bill.If it was a pipe in the building and not in their unit, then I would think the landlord would be responsible.

Depends on property age but I almost always do a sewer scope, especially if the pipes are cast iron.

One must pause when someone offers advice on getting rich the most likely case is they are making more money selling you a pipe dream, if it was lucrative why would they not just be doing it.

By no means is this an exhausted list. 

However, they would actually handle things like plumbing pipes, towels for that pool, laundry, and some others.

You can write it up in the Purchase and Sale Agreement.I would exhaust all options with the seller before going hard or private money.