What are some little "inexpensive" add-on / upgrades can I do to the home help increase the rent while at the same time giving them the security that I am trying to make this place better for them?

We had a small fire in the common area of our association that caused damage to all six units.Some owners decided to take advantage of the situation and add on minor renovations to the repairs.The insurance company (Erie Insurance) recommended that we hire (Perfection Restoration).

It may sound nice to pay a 5% management fee but the extra fees can add up to be more than the other company that charges 10% with no add-on fees.

I don't know about the specific add ons you listed, but I do know that my insurance went down when I switched from a homeowner to landlord policy on my single family homes. 

Being conservative I would choose a large Well known company, insure the heck out of it, and make sure you get the vacant over 30 days add-on rider. 

For encapsulants, there's an add-on training you need to take. 

To add on to what @Rick Momsen has said.

I also plan to choose the coverage I feel is enough and look into the optional add-on’s depending on the area.  

Why would you decide to lose the income from the other unit and add on construction cost to add space?

I didn't need to add one because we're with in .5 miles of public transportation.