Performing adequate due diligence is paramount in commercial REI in order to determine true expenses (or accurate estimates) and to be able to adjust the asking price for deferred maintenance issues, etc. 

IMHO - the "vacancy rate" is a moot point, since it is what you want to make it.If the rent is under market value - then the rate is very low.If the rent is too high - then the rate is high...As mentioned above, boots on the ground is paramount.  

And the company you hang your license is paramount to how you run your investor business.

Of course the condition of the the home and price are still paramount. 

Peace of mind, protecting my equity and personal assets is paramount.

Their involvement in helping me build an individualized investment strategy has been paramount in getting me where I am today along with the resources they've shared for tax strategy has likely saved me 6 figures in taxes over time!

So your ability to both understand the process better than anyone else AND to convince other people to go your way, agree to allow you to do your project, or support your project with investment, is of paramount importance.

Therefore knowing FMR for the area and getting the rent-roll are paramount to understanding what day-1 ownership will look like AND how much better it can get with forced appreciation.

I recommend Dan Bostick at paramount title in Indy.

If I was the current owner of the property you're looking to buy the value of that would be paramount.