How cani get rid of cats that just started to hang around my apartment building?

For awhile now we have had cats that hung around our trash dumpster in the apt complex. But they walk anywhere now. Some of the people downstairs decided to give the 2 cats water and i guess some food and now they won't leave.They are hanging around people's doors and meowing whenever they see me. And my mom doesn't like them. How can i get rid of them? I was thinking of calling animal control but would my apt complex office like that? does it cost?