I wasn't sure where to post this but here goes:Is the losing party between buyer vs. seller.

You might want to see where the water lines are coming from in your unit, make sure that you have sealed around that as well.In my condo association, they determine who is at fault for the treatment of the building by bringing in a third party inspector (pest control) and whoever the pest control determines to have the worst/biggest infestation of (thing) is generally at fault.

If you choose to work your own deals which 99% of people do you'll have to disclose to everyone involved that you have an interest in the property or you are the purchasing party.

By fool proof, its basically apartments without the people, you have a unit that's full of items, without running toilets, leaky faucets, without tenant headaches, statistics show most people stay 12 months business stay 24 months on average, the best part is most people do not visit their belongings.

That's who's paperwork you'll be asked to sign and who would be the party taking the assignment and actions I mentioned above.

They may also be interested in seller financing... can be a great option for both parties.

I'm not a lawyer, but I'm sure some of this will help if you choose to proceed with an eviction or go back to collect unpaid rent from either party. 

As the others have stated, a 3rd party bank hired Appraiser would most likely utilize the Income Approach with secondary support from the Sales Comparasion Approach.

I'm not sure what the actual height of the flat part is since I did a virtual tour.

if its managed by 3rd Party pm you should be able to get a Trailing 12 months of income and expenses.