Seller finance into a BRRRR

[Josh Coup]

Dear BP community,

I recently met with a college buddy who is a successful REI with about 28 doors, has built some ground up, and is beginning to do some commercial. When I asked him how he got started, he said he just kind of fell into when someone offered him a multi-unit via seller financing. He did use private money for the down payment. My question to the community is: is it possible to BRRRR a seller finance? What are common ROI ramification of doing so? What are other tips and experiences others have had? What are common interest and term arrangements with seller financing?

Thanks in advance!