May have found a deal but he wants a variable rate

[Gerardo Lewis]

Finally after a few calls, a few meaning many calls and I still have more to do I have had 1 owner tell me that he isn't particularly interested in selling but he would definitely listen to any offer I can make especially if I can make one he can't refuse. So I know those aren't the best words to hear because to me it sounds like he wants me to overpay him for his property. I have done some research on the property so far but not everything I admit that. I also feel like this could be a good way to practice for me also. I'm new to trying to secure owner financing and he wants a variable rate how would I find out what is acceptable for this point in time? And would it make more sense to find out that info and verbally tell him to see if that interests him or should I get it down on paper in agreement with clauses to protect myself?