I'm not sure if they are loosing there marbles and if I should step in and offer a difference of opinion or offer reassurance.

Loosing the house and you getting it may result in major anger directed your way. 

Lenders do not want there to be loose wires, no roof, boarded up or cracked windows, no kitchen or baths, missing flooring.

It's a loosing battle trying to get him to throw anything out and change his ways, it's a psychological issue.

Tell everyone your goals and you are bound to meet a partner.

If you are seasoned from a lot of flips you have the means (contractors, knowledge) to deal with about everything efficiently and deep enough pockets that you can afford to loose money on one deal. 

Otherwise I assume going to the owners residence would be considered out-of-bounds and potentially a little creepy?

Are you saying very home in america should have powered lift chairs installed just in case a wheelchair bound person moves in to it in the future?

We are bound by a thing called “Ethics”. 

Don't loose your dad's money.