Has anyone ever disputed a collection with procollect, were they successful, any suggestions for this situatio

Ok, so 3 years ago my husband and I broke a lease with an apartment complex because we had just had a baby and I was in the living room feeding her when all of the sudden gun shots are flying right outside of our window. We made a statement to the police because we saw who it was that did this (our downstairs neighbors children) Anyways, so we ended up breaking our lease a couple weeks later when we recieved a newsletter stating that no crimes had been committed. We tried to make arrangements but were unsuccessful and the apartment complex did not want to work with us. We only had 2 months left on our lease, then when I checked my credit report there was a balance of 5,000 from procollect. No letter stating why they charged so much. So does anyone have any suggestions? Would this be a successful dispute or what do I need to do to get this off my credit. I will settle if I have to but I dont want to at all. That place was disgusting, roaches, ants, no ac. Aweful place to live