Owner Financing Family Farm

[Garrett Shackelford]

Hello all! This is my first post after several years of being a fan and finally completing my first live in flip. Excuse me if I post this under the incorrect category.

I’ll try to keep this short. I’m looking at purchasing our family’s farm (by farm I just mean land with a house). It is 25 acres and has a 2500sqft 3/2 with an attached 3800sqft shop. 
I am looking to owner finance this from my grandmother for $400k. This is a long term deal for me as I expect to do another live in flip on this home while investing in other properties on the side. Potentially developing short term rentals or selling plots of land from this property. 

My biggest questions are below: 

- My grandmother does not have the best health and is 74. In the case I owner finance and she passes. What would happen to the loan if I am the sole heir to this property? 
- Will she be allowed to charge me a 0% interest on this loan? 
- Will this loan require credit pulls and banks or can this be done with a simple contract and an estate attorney? 

It’s a very weird situation, but to sum it up I live in the home already, helping to care for her.  the property is entirely paid off. She wants me to get the home and land but want to give the money she would receive from my down payment ($80k) and monthly payments to her estranged son’s children. This is the only way she views it as fair to the family without selling the property as I’m getting a much better end of the stick. Any help on this would be greatly appreciated! Thank you!