In your case unless you are able to do 24 hour turns you may lose a months rent plus painting cost could be 3k, so I less turn would pay for the central air.You also need to consider the opportunity costs of not having $4000 to invest in another property.Good luck to you either way.  

Trust me, it will show much better when they leave and you have gone in to touch up paint and clean the place.

They painted everything gray and the inside had wood flooring.

(water in the basement but French drain is installed) Everything else is painted and she has new carpet down.

Some of my buyers are complete opposites where they only want C properties that need a ton of work, while others specificly want B class neighborhoods like shadle and with paint and carpet rehabs only.   

I originally hired him for his forte in painting.

I guttered alot of walls and a few ceilings, painted, left it empty during this for 2 months.

Tile is peeling, walls have missing paint, deck around pool is uneven.

If it is lead paint on the inside the remediation could be huge.In some cases if density levels have increased for zoning the answer might be to tear it down and build new.

You are going to want it cleaned and filters changed in order to help get rid of the smoke smell.You are going to want to wash every surface that you can get your hands on -- walls, windows, fixtures, painting may be easier depending on how bad it was.