Get out of your comfort zone.

If either of them were to stay involved, it could cost you money and you would collect less.Send it to collections yourself.

I'd recommend finding an insurance broker and stay away from agents.

You can not partner with relatives or have them do any work on or stay in your properties. 

How long can you comfortably stay in this house?

If you can show / prove to him that the park will be worth more because you are rebuilding the bathhouse, paving the roads and adding a playground then maybe he will feel more comfortable? 

Update: We ended up backing out of the commercial deal, way too many issues going on and shady practices that we were not comfortable engaging with.Now the question is what to do with the chunk of money left after we pay taxes.

There really isn't enough information here for someone to give you a proper answer.What you need to do is calculate those tax savings over the next 5-7 years (or however long you plan to stay in the house) vs. what the interest rate reduction will save you over that time period.

I look for locations that I am comfortable with, and look for the best rental yield I can get in that location.

They can live in the unit, stay at a friends or family members, or rent a hotel themselves.