Once the drywall was out, the insulation has to be brought to code.

She had transformed the basement into an office with sheetrock, overhead lighting, installation of a closet, insulation, etc.

Currently my units have a lot of old plaster and are not insulated.

Less perfect as a long term rental since it a super old construction style with absolutely zero insulation. 

The one downside I can see to thermostats like this is the maximum temperature may not be enough for some poorly insulated apartments or large apartments with one thermostat. 

You do this from inside the attic, make sure you peel away any insulation that is covering the soffit vents...then you staple the baffles to the rafters. 

It appears to be in good condition and he is not seeing any spots missing insulation.

It appears to be in good condition and he is not seeing any spots missing insulation.

The permit application for landlords would include a completed self-inspection checklist certifying that the unit complies with the standards in the ordinance (including energy efficiency standards for attic insulation and attic access and efficient shower heads, faucet aerators, and toilets), documentation of maintenance of the HVAC system, and payment of a fee, which will start at around $70 per year.

It is not that crazy.Dont lie like "I found this way" or it was already done etc.......They know  what is done, if you are up front they can be nice and help you out.Since it is complete rehab, you will be opening  drywall,not everywhere just specific areas, and along the side, they will tell you where, open that up, and as long as it is insulated, rest is done correctly, you should not have much problem.Obviously, there will be some cost to redoing the drywall etc.... but you should have pulled those permits anyway.Good Luck though!!!