Sanitation would help, clean areas with grease and food debris. Eliminate water source(moisture), bait with approved roach bait killer Maxforce Roach Bait( ask pest control company). Dust voids with dust bait such as avert dry flowable.
I work with Combat and our Roach baits and gels are formulated to kill the source of a roach problems. I recommend that you use Combat Source Kill Max, it will work to destroy the source of your...