I had considered maintaining a certain dollar amount in reserves and semi annually diverting 75% of the income to the beneficiaries and the other 25% into a separate account designed for expansion so that the pool does not get too watered down as the family grows. 

The estate attorney recommended that we put the MIL's half of the property in another irrevocably trust and my wife as the trustee and beneficiary.

If you cannot refinance it is unlikely you'll be granted the novation and it will take a lot longer to get an answer on that.The beneficiary of that assumption has to fully credit qualify so, while yes, I agree that might be an option, it's not a given.

A title company will use your purchase contract to determine who gets paid out on the HUD and the deed will transfer to your name after the property closes.The seller will get a first lien position on the property (unless there is existing bank financing in place, but that's a post for another time) and should also get added as an additional beneficiary on the insurance.

In the big picture, housing should be a net beneficiary in this, potentially less intense and less prolonged, economic downturn.

Now, if you're a bank, no big deal, you only lend 80% of the purchase price and require an insurance policy be purchased by the borrower naming the bank as beneficiary to cover the balance of the 20% - also known as mortgage insurance or PMI.

Regarding protecting yourself- Make sure your tenants have renters insurance and you are named as a beneficiary on their insurance.   

You can certainly name your sibling as a beneficiary of your SDIRA. 

I doubt there is anything about a maximum amount of times.. so as the beneficiary of a property they might have the right to have the trustee agent advertise more than the minimum.. ???? 

I have been the beneficiary of the 11.7% appreciation experienced here in the last year on a portfolio of rentals over $1M so maybe I’m biased?