Amazing Deal: How do I set up?

[Matthew Louks]

A family member wants to sell me a property he owns free and clear for 20k that needs 25k in rehab. The ARV on the property is approximately 130k. He is also willing to owner finance at 0% interest, and $0 downpayment as long as I pay him the same $550/month as his previous tenant. I estimate 2-3 month before repairs are complete and I flip the property. Im not sure how I should or how set up the financing as I have only used conventional financing previously. I'm not sure how to setup the mortgage or financing legally for a smooth transition when I sell.

Thanks