As supply lines run through here my thought is to put a vapor barrier on the ground (none currently) and insulate the crawl space walls to make it part of the living space that is the basement which it is open into.

As Herb and Eunice said, you do not HAVE to pay.

Not to mention the smell in her u it is so overwhelming my flammable vapor sensor in my water heater trips from the over whelming smell of cat litter.

Black mold was found behind the sheet rock and into the vapor barrier.  

For starters, the slab will never be considered good for a 'living space'...... no vapor barrier, not enough steel.Better to have a contractor come in and make sure the electrical is ok and then leave it at that.You could go down to the city building department and ask vaguely about converting a garage and see what they say.

Wrong concrete PSI, wrong steel pattern, no vapor barrier, etc.....we usually had to tear down and build new.

Water vapor condensation should be kept outside an interior wall by the Kraft paper on the insulation. 

Security deposit gets returned in the timeframe from her being “vacated” right?

This included fiberglass insulation, new drywall, new vapor barrier.

Are you going to install some type of vapor / smell barrier as well.