Ask for Eric! He is your man. When I bought my house, we had ants outside everywhere, a total of 19 nests. he came out monthly until he found the right remedy, but before Fall of that year (6 months later), we had the nests down to 4 and well contained. We haven't sprayed for ants in over a year and 2 nests have reemerged. if history repeats itself, One treatments, maybe two, then another year with no treatments.
Last year we had mice coming in the house. Eric found the entry location, baited the mice, and they disappeared within 3 days. With Bug control, Terminix has the right treatments, but they need our help as the owner to point out all that we see and know, then Terminix can solve the problem, they have the right tools.