Is it common for tenants to stay in the unit if the extermination process is three weeks - three separate treatments?

Basically double, which was the goal.5% of the units will get this treatment.

I am considering doing a DIY treatment right at the beginning of the project so if i missed something, it would take care of it when i put it up for sale.

Was this an investment or an opportunity to help your father.And John is right, there are other ways to establish it as investment tax treatment wise. 

Although this person likely has the access to the capital my business sorely needs, I am moving on and continuing my search.

Note: this year there was a change in regards to evidence of termites and treatment so if at all possible you will want get proof of treatment from the current owner and give it to the inspector before the inspection.

Also the treatments on passive loss limitations can differ to dependent on material involvement 

The interest will need to be traced to accurately determine tax treatment. 

It takes up most of the room and is an eye sore, and I wanted to see if I were legally able to remove the stairs and just leave them with the deck.

That gain will likely push into the highest tax bracket and a large increase there and/or less favorable capital gains treatment could be a big stinger.5.