The $6000 was a 1,400sf home, all new wiring, new interior and exterior panels, 200 amp service, permits pulled & rough-in through final including installation of all fixtures. 

I would spray paint (little cans) the tracks and install more modern ceiling tiles.

I've learned to install 220 volt service to an appliance from the panel from scratch. 

There window units already installed 1 in dining/living area and 1 in each bedroom 785sq ft.5,301sq ft lot

Negotiate with the seller to get it installed before closing.

Closing open permitsRe-pave the lotAdding parking spacesThree 50 amp plugs for food trucksExterior PaintInterior PaintGarage Door, install.

There is some mold growth on a first floor wall from a leaking toilet shut-off valve in an upstairs bathroom so in the scope of work are you able to state something to the extent that to completely remove the mold it will require new drywall and removal/re-installation of carpets?  

I don’t want to carpet because of installation costs  and maintenance costs but i hear that it combined with good quality padding will help reduce sound significantly.  

If you pay for the installation and maintenance (assuming they already pay utilities) then I will knock $100/month off the rent for 50 months.

If the top part of your door frame is at a 5 degree angle or worse vs being straight you have larger issue then floor install.