> No way to keep them from moving from apartment to apartment via cracks in the walls. Not totally effective because it's almost impossible to be thorough enou

> No way to keep them from moving from apartment to apartment via cracks in the walls. Not totally effective because it's almost impossible to be thorough enough, but you can use painters caulk to seal up every crevice you can find. You'll also need weatherstrip around and a seal under your exterior doors. Unlike rodents, roaches don't gnaw through walls. Regular applications of insecticide help also but a lot of people don't like that.