Is it a contract for deed, or was the seller financing the sale?  If the sale was complete but financed by the seller it shouldn't change anything except who gets the payment.  And if all works correctly shouldn't change with a contract for deed.  Well, other than the hassle of getting the deed signed by the heirs, or their heirs if they die before it is completed.

But if a contract for deed what happens if one of the heirs files bankruptcy? That's always been my concern with a contract for deed.

I have to admit a bias against contract for deed, because I saw it happen.  Farmer bought ground, put an irrigation system on it, and the owner filed bankruptcy.  He lost all cash paid and the ground.  He was able to remove the system ... but not the well.