Renter Breaching Contract & Moving Out Early

[Gabe Bouldien]

Hi BP, I am a landlord of just one property in TN. I found a tenant in September 2021 and we signed a one year lease agreement through September 2022. He paid me 6 months rent ($1700/month) in full upon lease signing (so he paid to cover the rent until the end of March 2022). Well a few days ago, 1/3/22, he let me know that he bought a house in the area, and will be moving out at of my rental at the end of January. He said that he expects that I refund him the March rent that he prepaid since he is giving me more than 30 days notice. 

I don't know what to do, and need advice. He broke contract, and I believe TN states that I don't have to pay him back unless I find a new renter to "mitigate damages". I also don't want to piss him off and him punch holes in the walls, etc (cash for keys option for me?). 

Like I said this is my one and only rental. And this is only my second tenant to deal with, so I am still a landlord rookie. 

Any advice is appreciated.