That's why I don't personally use money orders. You will have to somehow prove that you delivered the money order to the landlord. (I believe that placing in the depository designated by the landlord for receipt of rent checks should qualify.) Then, the risk went to him. Your two hurdles: proving that you put the check in the box (was anyone with you) and getting by the bias of all Justice Court judges against landlords. Without a lawyer, I don't think you have much chance of winning. With a lawyer, you have some.