Remedial Action must be started within 24 or 72 hours depending on the situation and repairs must be completed within a reasonable period of time.    5. 

They definitely dropped the ball and Scott has worked hard to try and remedy the sutuation, although their loan structures changed in the middle.of my deal, and theres not much that can be done now.

We're facing an artificial contraction that can be remedied almost overnight(under 6mos).

After talking to my insurance adjustor, he advised to get details on HOA coverage b/c to remediate damage we need to go all the way to studs. 

If you're going to remediate a sink hole, you should remediate it right.

But in a state like Cali, you might be forced to get a professional remediator (probably should to be legal).

welcome to the world of insurance, where everyone is trying to one-up the other guy. this happens across the whole insurance spectrum and not limited just to home insurance. to the OP, shop around and get a new carrier, then start consulting with experienced roofers in your area on what you remedy could be.

Of course, this assumes you're keeping track of everything religiously, as it would be hard to reconcile such records and ensure completeness.Otherwise, look into hiring a bookkeeper/accountant/CPA who can provide this as a service for you and can help advise you proactively, so you can prevent issues rather than remedying them after the fact.

Have to retrofit things, and abide by (or remedy) the structural decisions made over a hundred years ago.  

My question is, are there any other potential causes for this sewage backup, and anything else I should be thinking about that could make it much more costly than $1,000 or so to remediate?