There were exposed water lines and pipes in the rooms and missing doors.

Assuming adding a vent isn't unduly difficult, i.e. the dryer being in an interior room far from an exterior wall and/or no good access to run dryer pipe, I would put it in on my own.

There was another property where I was waiting to participate in the auction, the counter reached zero and it says live auction will begin soon, again nothing ever happened. 

I imagine a lot split would also significantly increase cost of utilities as now I would have 3 hookups in that scenario.I am also concerned what would happen to that sweet 3.25% 30 year fixed mortgage I have, which I don't want to create any risk over in the slightest.Any advice on how to frame my counter arguments would be incredibly appreciated.

I had an estimate done ($7k) because at this point the sprinkler piping is exposed and I'm afraid that could lead to an even greater problem.

Hot water heater, furnace, gas, electrical box, HVAC, oil tank, plumbing pipes.

Wondering how to build trust in him to do seller financing with us after this.For reference we have 100% close rate, my thoughts approaching this is to counter back and say the risk of default is very rare, if he's worried about the park defaulting he just needs to save up $20k in reserves and he'll get paid $70k in income for the park for the next 5 years while he waits for balloon.

We relocate tenants if there is a hazard,  always use your own home as a guideline would you move out to get new floors probably not, now if a pipe burst and created mold you probably would. 

I've been submitting offers and not getting counters.

The daughter, who again wants nothing to do with her mother, counter offered me with $8,000, and that would be something that she could "talk her mother into doing".