Would like to do rent to own. How do I approach the sellers?

[Aja Yasir]

Hello.  I found a single family home and a duplex today that I'd like to put offers on.  One is a single family.  The owner is moving into a nursing home and medicaid is pretty much forcing him to liquidate his assets.  The other is a duplex.   The owner passed away and the heirs live out of state and are trying to sell it. I'd like to do no money down/rent to own deals but I'm so confused about how to approach the owners with that idea.  Husband and I put an offer on a 14 unit last week and it was rejected.  I know it's a numbers game but I want to be able to really make the offers sound good although they're no money down/rent to owns.