The owner never bothered since they were only there during the times of the year when they felt it wasn't needed. 2) There is no washer and dryer, 3) the home is a 2 bed 2 bath plus a basement, which the basement needs some paint on the walls and new carpet, but not much.

I'm running into hangups with code section R302.3.1 which seemingly requires not only the floor separating the units to be fire rated but all the walls below supporting that floor to be fire rated (ie all exterior walls and load bearing interior walls on the first floor), which may mean extremely expensive fire rated windows at the lower unit.  

.,  where I can see this for sure is with agents on BIG teams that are beginning their carrier they get cash flow ( IE they get paid I suspect from you weekly or monthly out of the retainer).... ya I can see this.and as you said your blue color FHA buyer with minimal cash savings is probably not your target.. but sophisticated number crunchers..

., which would not work, since we don't have the wall or a flat surface in the location that we would want to install it at.Option 3: https://www.mailcase.com/about/ , which could also work if I purchase the spreader bar.Questions:1.

If there is mold, it will usually be A) on the subfloor exterior, joists, and insulation in the crawlspace, or B) in any areas of water damage/water leaks inside the walls, behind tile in bathrooms, etc.

It's definitely the cheapest option.Mini splits require some amount of duct work if you are going to serve more than 1 room on the other side of the wall from the unit.

I remember some stars on a wall. 

The easy answer is simply a 240volt plug on the wall.

Keep a door between units, or maybe have one wall that is easy to remove that opens it back up.

This isn't like a court battle where everybody has their back up against the wall ... trustee and lender may be willing to work with you.As the property owner you have the right to protect your interest by reinstating the existing loan, that's not to say the lender, after reinstatement, can't start a new foreclosure based on a violation of the due-on-sale clause, but may not.