My long time restaurant tenant wants to buy the building I am renting and asks for owner financing

[Jan Lee]

The tenant is a fairly popular seafood restaurant in town that is family run business and has been a good tenant (always paying rent on time, easy to deal with etc). They have been there for over 15 years. They are interested in buying the building which they plan to upgrade. They asks for owner financing.  I would need to pay the bank about 25% of the sales price. What are my risks? What should be the terms the financing?