Pest control companies generally divide into two categories: insects and small pests that one wants to exterminate; rodents and larger animals that should be captured and released.
When store bought remedies fail to work, you need the help of a professional. They will have different chemicals to work with, some restricted by law to professional use, as well as specialized traps and poison containers designed for specific target species.
Try to trap some sample insects before calling an exterminator. That will allow them to focus directly on the critters you want to control.
Our guest, Dave Smusiak, was from the Toronto area franchise of the Rentokil company.