I'm dual licensed in NY and NJ and so is my another agent on the team.

HUD does not factor into the rent other amenities that might be included in the rent such as garage, basement, fieplace, central air, pool etc, that might command higher rent in the non-Section 8 market place. 

You can use bat insulation or spray foam, which has the added benefit of giving you an air-tight seal and also keeps the bugs out. 

And also being next to a base Im thinking about short term renting, or Air BNB How did you finance this deal?

-Structural (foundation, wall, ceiling and floor)-Roof and Exterior(Roof Condition,Gutters and Downspouts, Siding, Windows and Doors)-Plumbing (Water Pressure,Leaks, Drainage, Pipes)-Electrical (Wiring,Outlets and Switches,Breaker Panel, Lighting Fixtures)-HVAC(Air Ducts, heating and cooling)-Water and Moisture Issues(Attic, Mold and Mildew)-Kitchen and Appliances-Bathrooms-Pest and Insect Problems-Safety Features

Adding a 1/2 bath, new roof, central air or other typical improvements will increase the value of the property. 

I retired in 2008 with 21 years in the Air Force.13 sales in your first year is pretty impressive, particularly for someone on active duty.

Is it worth it to put in central heat and air?

The cold air often runs out in the summer and the heat doesn't turn on in the winter.

Let's clarify the air-conditioning equipment.