I saw a rat run rom under my bed

I've NEVER lived in a house with rodents so, when I saw it I FREAKED OUT! I live on the third level of the house and I have so I've never seen any rodents. My roommates on the bottom floor said they have been seeing them for over two years! IN THE HOUSE! My ex-told me when she moved out 9 months ago she saw one running in the hallway on the bottom floor. My landlord had an exterminator come out and he covered a hole under the house and killed the rat. I believe there are more of them in the house. I want to move ASAP. I've been staying in a hotel for the past 8 days. I went back home to get clothes and I saw droppings. I'm not sure if it was from the previous rat or a different rat. Anyway, I still have to pay my landlord rent because I have two months left on my lease and he won't give me my deposit back if I break the lease. I'm trying to figure out how to tell him I'm ready to move.