If so, I wouldn't be scared in the least to deal with that as an fyi.As a last note, in Florida building code requires on a mold remediation to cut the drywall up (x) inches above the mold area and replace that drywall so make sure to check with local municipality building codes when get repairs done.Best of luck!

Did you say it has only sunk 1/2 inch?

Never give an inch. 

During the rehab we built a small concrete ramp (only had to go up a couple inches), widened all the doorways and built a roll-in shower to make the unit accessible.

At this point you can place yourself first or do what is best for our industry.Do a proper eviction, give notice to inspect, document every square inch of the property with a video camera first then begin the reformat notification process.

The 1/2 inch stayed till noon the next day.

As for the fridge, a 7 cu ft should be fine, and about 21-22 inches width I'm guessing it should fit between counter and window.Regarding the load bearing wall between room and kitchen, you can inspect it from the top by removing ceiling tiles (see pic 5 in OP).You're on the right track, just go ahead and put your thoughts in drawing, including dimension/location of doors/windows and current kitchen counter.

Agree with @Christopher Phillips,Don't pay attention to ANY hairline cracks, meaning 1/8" of an inch or less, specially if they are on plaster or gypsum boards/dry walls.  

double check first, I thought I had 2 inch maple and it is 2 inch white oak

You are the "boss" and can create the rules.Overall though, with people, if you give an inch they take a mile.