You'll find this article to be very informative and crucial to reaching your goals: The Core 4 Members Vital to a Profitable Long-Distance Real Estate Investing Team. 

My take is that it's vitally important to know who you are working with, and have the history of the players involved.

There is always the Heloc path but those can gett you into trouble and have restrictions like shoter amortization, Prepayment penalties, interest only, (Can create bad habits of low payments) which causes a standstill balance. 

Engineer reports the structure is sound and the floor is not risking the property's integrity for habitability.

The $20 you gave him went to his favorite habit - cigarettes, liquor, drugs, cat food.

Ringer's book, 'Million Dollar Habits.'

The lease should adress whether the lease cancels if the property is not habitable but i would hope it does in your case.

Patience and staying well-informed are vital in real estate.

I would explain to the tenant that these issues do not affect habitability and that if they withhold rent they will be evicted but that these issues are being addressed.

These are vital for investors.