post occupancy contract question

[Jacob Straussen]

Hi, I'm new to buying and selling and just had a dumb question.  I was just wondering what happens if a seller/tenant moves out early with a post occupancy contract already signed?  The contract allows up to 20 days with a certain rate per day as well as a security deposit.  

Is there also any circumstance to cancel the post occupancy contract or if it's beneficial to keep it.  I feel it provides protection as a buyer but just wanted to get everyone's thoughts.