There are places that offer free legal advice from actual lawyers (kind of a community service thing) - I would call your state's bar association and ask if they know of such a service. It would seem, if there is ANY clause in your lease about them being required to give some notice - which most leases have - that you should be able to recoup some of poor Graham's vet money, or at least a settlement of some kind, after they have again violated your apartment and your good will.

I bet everyone will be glad when you are in yourown place - you, Graham - and everyone at Pet Talk, too! Poor sweet boy, give him a nice tummy-skritch from us.