Lease to Own option

[Shuai Zeng]

If any of you can shine some light on it for me, it would be great. I'm looking at a property from a third party. Here is what I was told of. The owner purchase it as a REO, with 90 days no resell. He purchase it with hard money around 10-12%. He some how want's back out of it, so he's selling it with a lease to own contract. I have never made a lease to own purchase before. Do the down payment need to be paid at the lease, or is it a option to be able to purchase at end of 3 month?