Offer to purchase contract through onwer financing

[Abad Marroquin]

Hi everyone. I need to submit an offer to purchase through seller financing. I have no clue how to start. I have used the offer to purchase contract for single houses from the Biggerpockets, but I am not sure if I can use it in this situation. How can I structure it? Let's pretend I am planning to offer $300K with $100k down payment at 4% interest for 20 years. This property is in Tennessee. If anyone has one and would like to share it with me it will be greatly appreciated. Thanks in advance!