Need advice on how to buy from my friend using seller financing

I would like to purchase a property from my friend who has a mortgage on the property and would like to sell me the home for no money down. We would like to set a kind of promissory note situation wherein I take possession of the property with rights to refinance or resale once renovations are complete. I would pay 5% interest above the agreed-upon price and the note would have a duration of one year.

Can anyone direct me to a template for a contract we might use to get to closing?