Otherwise, it will be a continual thorn in the side every year, and it has the potential to damage landlord credibility.In your conversation with the landlord, emphasize that it is in both parties' best interest to diagnose and permanently fix this situation.

or is this a property that can be permanently split and rented out as a true duplex? 

The monthly rent on that house is only a few hundred bucks more than the mortgage payment (as you would expect with a no money down loan), but I try to take a longer more permanent view of my investments.

My advice is this...never let a temporary change a permanent. 

I'm sorry to hear you are having issues, hopefully you can fight it, but in my experience on the lending and investing side, the appraiser won't budge unless they made a trivial mistake (forgot to take into consideration major highway dividing lines, incorrect square footage on records, fat fingering an address, etc.)

For other types of foreclosure prevention alternatives, a lender must record a rescission of a notice of default or cancel a pending trustee's sale if a borrower executes a permanent foreclosure prevention alternative.

That means they have permanent foundations according to FHA.

I'm on it like a fat kid on a candy bar!

I recently spoke to my lender about permanent financing on a 440 SF home.  

A slip and fall isn't going to wipe out your underlying coverage but if someone dies or becomes permanently disabled the numbers could get very high.