Advice to close this Seller Finance deal

[John Dunbar]

We seem very close finalizing a Seller Finance deal, but cannot get the seller to realize that he will no longer have financial or legal responsibilities of the property. It seems like the perfect situation. 65 y/o man looking to retire and travel, plenty of money, is not utilizing the money to invest elsewhere, wants to reduce tax bill with sale, and wants to be "completely done with property". We have offered well over asking price with monthly payment close the the cashflow he is currently getting, but he is still not budging because he wants "no ties to the property". Property is a mobile home park listed at 1.5 mill

Any advice to get this deal done?

Any legal documents we can provide to show that he will be "done" with the property?

Any different strategy we can utilize?