My fiance and I rent a house in town. Our neighbors house is about 20 ft away. 9 months or so out of the year we don't have a roach problem but during the fall after it has cooled off until it freezes you can stand between our houses and watch the roaches move from their house to ours. Our land lord called the city and code enforcement harassed them for a week or two then seems to have dropped it. I've tried both ortho home defense and raid bug barrier sprays and the landlord also sent an exterminator out once to spray our house. Is there anything I can use to keep the roaches from migrating from their house. Even the professional didn't stop them completely. They did slow down some though. Thanks for the help!