Beyond that, it is very much up in the air. 

Like an Air b n b? 

It has at least one ceiling vent that I understand is connected to the rest of the central heat and air system.

Lower your expenses by changing out fixtures to low flow, changing out lights to LED's, upgrading heating and cooling systems if central, changing windows and insulating if central heat and air. 

Probably related to the renters removing the AC air filters instead of replacing them or letting me replace them. 

@Odie Ayaga I am estimating about 30,000 I’ll be able to do some of the work myself to cut costs especially since I’m on mechanical contractor can do the air-conditioning myself even if I have to get contractors to do the rest

@Katie MillerSo I retired from Active Duty Air Force on 5 May 2020, so right in the middle of this thing.

The air-conditioning was replaced along with the roof.

I’m interested in purchasing a home in the New Orleans area to use for an air bnb.

This matters because of the cold air return/venting calculations for carbon monoxide/dioxide emitting  heat sources.Pics would be helpful - is there no way to make another entry point to the mechanical room, close off the entrance to it from the bedroom and add a separate closet?