I wouldn't fight them on moving out that's for sure because you will only lose more money in the end. Like others said post a pay or quit notice and then file for eviction. Let them know you will file for eviction if they do not pay up and that it will ruin their credit and make it very difficult to ever rent a decent place again. If they do pay up but still want to leave let them. What kind of stipulations did you have with your agent when finding a new renter? Have all your stipulation down on paper and that they are liable if they rent to someone without those qualifications. If possible do it yourself. They just want someone in quick and with the minimum of work so they get paid.