Or, depending on the property you could go non-QM with like a DSCR loan and close in an LLC or partnership.

This term replaced "subprime" and looks a lot different than subprime loans of the past.

10% down 2nd home loan and savings from the proceeds of already owned STR's.

If they can afford to stay, chances are they need to refinance and get the X name off the loan.   

Be sure your lender is comfortable with this, as many fear giving folks primary loans for properties they view as having a high probability of being turned into a purely investment.

You can spread your cash out pretty far here when taking advantage of leverage opportunities like 100% purchase/100% rehab hard money loans.

I understand it varies from city to city.

They will go up to 100% loan to value or LTV (or used to). 

Again, the $600 interest threshold is per loan, not per person.But this was not my money!

I ignore the gurus claiming the CMBS is about to explode again and all these commercial deals will flood the market, that's not how it works in our current reality, banks are not stupid, nor are the owners; the banks will work with owners that have those loans and modify them to stabalize the asset.