I've never seen a landlord go after a tenant for breaking a lease, honestly. The few I've talked to generally say they are beyond happy if the tenant is just out, and indeed, that's exactly what they say in eviction courts. They say they don't care about trying to get money out of the poor person being evicted, but that they just want the unit available to rent to someone who can pay. I think any landlord would be happier with a tenant breaking lease than doing AirBnb, for example.