multi family lot purchase, owner finance

[Cody Malone]

I have found two lots for sale, the owner is open to an offer for seller finance.  Im not sure how to structure this offer, ideally i will be building a multi family (duplex) built from shipping containers.  The lot is already zoned appropriately, and i am waiting on final designs for the project before i shop for the money for construction costs.  There will be no return on this property until post construction, at which point  I can refnance out the cash or sale the units.   Any advice would be welcomed and much appreciated!