Should I first secure a pre approval for what I am qualified for or should I just continue looking at properties.

The big picture is this: Airbnb/VRBO/short-term rentals can continue mostly unabated.

The slope of the land and how much dirt to be moved also comes into play as it can get expensive to level for site work.Additionally inventory levels of similar locations with vacant buildings where developers or tenants can go in cheaper and faster might be competition unless you have one of the best locations in the area.Basically what I am saying is that there is a lot to this and you need a specialist to help if you are trying to extract any additional value out of the property versus it's current use.

I will let the tenants pay the debt, write off the interest, and continue to grow a larger portfolio!

You will need to confirm with local building dept if you will need continuous insulation. 1) remove siding and install sheathing with insulation adhered to it. 

Continued diligence and activism will be needed as what did pass is not perfect and may be revisited in the future, especially the potential permit limits.

Given this is continuously rented, so might be in better shape. 

I think the insurance needs will depend on the overall strategy you are going to put into play and will change as the strategy progresses.

How should the 4 year lease being left and rent due for 4 years play in this scenario? 

So again knowing who is doing what will play an important role in how the splits are determined.