The Unsold House

I have had a rash of cases in the past few months where the parties agree to sell the marital home and then they cannot find a buyer.  What happens when it is not sold?  A property settlement agreement really needs to address this.  The best solution I have come up with is to add a provision to allow the trial court to retain jurisdiction if it is not sold in a particular time frame to determine how one parties equity may be obtained.  Without this provision, there is still some cases that say this is property division and may not be modifiable.