With most insurance, it goes back to the peril that caused the damage, and whether you have protection for that specific peril or not. 

Good old Uncle Sam.For most folks in the US, taxes are anywhere from 30-50% of their gross income every year.To protect yourself, you should do 2 key things.1.

Quote from @Sylvia Castellanos: Seller pays for title insurance to guarantee the buyer's protection from any title problems.The contract determines who pays closing costs.

Many cities have high overhead costs that consume a large portion of generated revenue.

We have a 14-page management contract that we've added our real experiences to over the years, with the intent of protecting both us AND the landlord.

The banks MAY call the loan due but it is not illegal to buy a property sub to the existing mortgage.You are correct, Subto IS legal, when done legally.Withdrawing money from the bank IS legal too, when done legally.Are you aware that when done improperly, Subto can lead to charges of Consumer Protection ACT violations, artifices, deception by omission, equity skimming, bank fraud, mortgage fraud, tax evasion and so on.

Are there any other considerations to ensure appropriate liability protection in this arrangement? 

I mean even those of us that are brokers if we don't protect our position in writing we will get cut out.. 

I did consider the fact that multiples can be complex and time-consuming (which I am leaning away from). 

@Alec Barnes one of the problems with communication is the different expectations.Agents and consumers all think PMCs should be available 24/7.NOT POSSIBLE for the relatively small monthly fees owners pay PMCs versus the thousands of dollars of commissions agents get per transaction.So, while agents may answer their phones 24/7, most PMCs do not.