Even if you allow a premium one the per ft^2 cost due to "historical rehab factor", it would still be scary.  

Hey @Jacob Tucker:I happen to be an insurance agent in Utah so hopefully I can give you a good idea on the premium.

Having premium finishes very rarely increases the value equal to or above the cost.

How long do the wood frame on exterior houses usually last?

We do some of the work ourselves, but we hire out for the major plumbing electrical, and wood floor refinishing.

Talk to your insurance agent, but when you purchase these policies they are typically for 6 months to 1 year and you have to pay the entire premium up front. 

Now both my wife and I have good jobs, her for the state, and me with a small company where I handle all operations so we are quite secure (knock on wood). 

The hot tactic is to NOT do carpet, but wood grain vinyl through out.  

The rental unit has just tile flooring and wood laminate. 

(especially if the property is build on a wood frame.  2) I'll pile on counting the PM in your calculations.  3) Finally, Be overly conservative on your MX and CapEx numbers...on a 40 year old property you can only come out ahead.