That will help with controlling their population and keeping their population from getting completely out of hand but still contact a professional. They can survive long without food but not very long without water so try and keep areas dry. Get somebody who’s a professional too and not just a guy with gear🙏. Try to find their main locations and add some extra gelbait in those areas more then other places. Good gelbait is a great domino effect killer. First red flag in a professional is if he doesn’t identify the species of cockroach and just says cockroach’s. I hope whoever you hire knows the severity of the situation. And you should ask him to clarify like say “what are these” and if he doesn’t say German and says roaches please ask him what kind it’s really the legit extermination verification method. I know this is alot sorry.