You should look at comparable sales of 2 unit properties in the area and use those to determine the ARV.

To be clear, there is no tension involved with this at all - we're just all trying to determine the best outcome for us the investors, and the kids as heirs.

I’m just looking for as much information to determine if I need to delay steps in my path to avoid crushing losses or change the path yet again (less willing since I I have done a lot of tweaking to this path).

Usually because of a motivated seller that just wants out or because the house is in such rough shape that there is a good spread.Their ability to buy low for whatever reason makes them money.  

I have confidence in my abilities and, in that sense, I am cautiously optimistic for the near-term future.

I think the deferred mortgage payments would be the bigger help as long as a) you're not required to pay all deferred payments at once at the end of the agreed-upon term; and b) it doesn't hurt your credit or ability to get a loan in the future.

Also, I am not sure where you live abroad but I would suggest working with your adviser/accountant to determine the best course of action for the currency exchange that will be involved. 

Yes it is a poor personal reference.Approve or deny the applicant based on their background check and their ability to pay the rent.

Also with the data - can the govt abstract the data to determine a remedy to limit damage ?

I would have the conversation with your lender to determine the best course of action?