I've never seen anything truly prevent termites, so you will not like what I have to say.
I live in a termite infested area: Lots of trees, moist ground, plenty of houses, and plenty of termite-treatment professionals. It is a wonderful sight to see each late spring when termites fly away from their nests to start new colonies. Somehow all the existing colonies do this all on the same day, so on a 5 miles dog walk this spring, I saw about a half dozen colonies exporting their progeny. I think this occurs after a new moon in late April. Termite companies know this happens, so they time their TV, radio, online, and print advertising to coincide with these releases of winged termites.
OK, now back to our homes. When I first moved here 20 years ago, I noticed termites everywhere around the house, but not in the house. The house had been treated with a buried perimeter of probably termidor by the previous owner. Nevertheless, termites were seen in most of the wooden fences and occasionally building tubes up the foundation. I spot treated, knocked down the tubes, and called termite inspection company for a free look-see. The guy came out and said, "I don't see any termites." So there you go. You cannot trust what anyone tells you.
That said, we have never had any other obvious evidence of termites in the house, but we see them all the time in the area, say within 20 feet of the house. They could be munching away and no one would know. I am vigilant and can do my own termite inspection as well as any pest company.
In the 20 years I have lived in this home, I have never paid for a termite inspection nor any overall treatment. I cannot say the same for my neighbors.
My neighbor woke up one morning with termites flying out of their master bedroom closet. They had been paying for years of termite inspections which never turned up anything. The critters were simply out of sight and out of mind.
Other neighbors decided to remodel their master bathroom. When they ripped out the tiles in the shower, they found a healthy colony of termites just living the dream.
The homes here are built on concrete slab foundations. One can easily see if termites have built tubes up the outer concrete. One cannot see if termites have built a tube up an internal crack or around a drain or water pipe through the concrete slab. An inspector cannot even see these internal access points.
Bottom line: Don't pay for anything until you get termites. Perhaps have professional dig trenches and treat your foundation once every 25 years of so. Sentricon would just tell me what I already know: There are termites in the environment. Even if everyone in the neighborhood was diligent, there will still be termites.
