How do you Owner Finance??

[Sanden Leavers]

Hi guys, I am a new investor trying to create an owner financed deal. However, I do not know much about owner financing and how it works. The deal I would like to structure is a $60,000 town house and the people that own it have a loan out to pay for it. I want to go in give them a down payment and then let them I've there rent free until they decide to move, then pro rate the amount of time lived there and then pay them whats left afterward. Is this plausible and does anyone know how it would work with their existing loan? Would I have to take over their original loan?