I recently moved out of an apartment and I had lost the keys. The landlord is now saying he will sue for not returning the keys. I lived there for 3 months as a subletter. I than chose to go to rehab. Paid one extra month. They found someone to replace me but still want the keys. I offered to pay for the locks to be changed but he said he will still sue me. Can he do this? If so what will he sue for?
He can sue you but what are his damages? You offered to pay for changing the locks. If you do that, what else can he want?
No damages means no case. If he does sue you, he'll have to prove that he was somehow harmed, and it's hard to imagine that the amount will be greater than the cost to change the locks.
Sounds like a misguided bully to me.