Ideas for how to structure a owner carry contract?

[Lance Nelson]

Newbie here... I'm likely going to make an offer on a duplex, but am trying to figure out how to structure the offer for an owner carry contract. The man is the sole owner of the duplex and he is in one of the units. He is paycheck to paycheck and trying to rent out the other side right now. The place is probably worth $460,000 so he's sitting on a good amount of equity. He has another lot that he wants to build on at some point, but doesn't have solid plans yet. The offer I'm thinking about would be for $460,000 with a 10-20% down payment and 3.25% interest on the remainder (owner carry) with a balloon payment at 3 years. We are doing this to have 3 years to secure financing (long story). The guy still needs a place to live so I'm thinking about writing a 3-5 year lease into the contract. Anyone have experience with this type of thing? Thanks!