Mortgage rates and PMLs are 8-12% plus points right now so the deal has to be a low enough entry. 

He takes the same risk as any landlord out there, since a lot of renters would not qualify for a mortgage and default anyway.

If you do want to go this route, make sure that the underwriting of the investment property pays back both its mortgage and the monthly HELOC.

List price: 445,000.DP: 89,000Closing: 8900Total Invest: 97,900Projected mortgage: 2500Rent: 1700 per unit, 3400 totalTaxes: 42Insur: 263CapEx: 100Repairs: 100Vacancy: 100Total expense: 3105Cash flow: 295, 3.1% - 6.0% CoC return. 

Most mortgage companies will not call loan due if payments are current but you do run that risk and need to be prepared to payoff or refi at a moments notice.

They do not want the other person's name on the deed or the mortgage once the dirvorce is finalized.   

I continue making the underlying mortgage payment myself (autopay) and get reimbursed from the borrowers payment.

Even with that, I think we will still be way ahead. 2 bed, 1 bath, 1200sq/ft, detached 1 car garagePurchase Price: $38,000Repairs: $20,000ARV: $96,000 (based off Zillow, but a local real estate agent thought that was pretty accurate)Mortgage: $430Insurance: $55Trash Included: $25Rent: $1,000We are now going through applications for our first tenant. 

@Collin Luckett  Just adding, if you have the ability to fund with your HELOC, it would be far cheaper than PML or Hard money. 

Both these properties have mortgages and they both are required to have insurance on them.