Consequences of defaulting on a private payment agreement?

I have a payment agreement with my old landlord for property left in the home when he sold it. After I created an arrangement with him, my hours at work unexpectedly dropped to nearly half. I went to him and asked if he would take the furniture back and he refused. As things stand, I will end up defaulting on this agreement. If that happens, what action can he take against me besides repossessing the furniture?