Then, there need to be no other debtors in line to collect the overage (or the laws have to support the former homeowner collecting before the junior debtor...maybe still on the books in some places but far rarer after the GFC).

There are cases where yes, you should pay off your debt prior to investing, and cases where, no, you shouldn't.For example, if you have "bad" debt (debt which is currently delinquent, very high interest - 7 or 8%+), credit card debt, or that which is imminently about to impact your credit) then yes, you need to pay that off before starting in real estate.

It does not need to carry a specific address and will attach to any and all real estate owned now or into the future by the debtor.  

I've found different lenders calculate DTI ratio when it comes to rental income differently.Some lenders take rental income (or a percentage thereof), subtract the mortgage amount, and then add the result to either the debt or the income.Others add the rental income (or a percentage thereof) to income and the monthly mortgage payment to debt.So, let's say a place rents for $4000, the mortgage is $2000, I make $5000/month, and I've got other debt of $2500/month.So, my DTI without the rental is 50%.Under the first scenario, .  

It's expensive to do (my average cost is about $800/ forelclosure) , but the foreclosure action is going to force the actual debtor to either pay the taxes, or I would get the property.  

Curious if the note group leans more towards taking on debt or JV’ing when purchasing?

Are so many possible debtors that can be in line ahead of you.

I have no bad debt or hardly any debt, BUT everything is owned by llcs and lenders will not loan.

If you have a personal homeloan (ignoring IP's for now) are you pumping every spare dollar into reducing that debt, or are you putting some of it into other investments (e.g. managed funds etc) as retrement savings?

There are only so many debtor-protection lawyers that handle these work and often times they will work out some kind of settlement with you.