Hi C.!
I've lived in Arizona since 1977 and never had a problem until we moved into our current house in 1999. Needless to say, I HATE bugs - but especially scorpions!
We've used a couple of companies in the past to treat our home, but now we have a little dog and the other companies were both using a dusting method around all the doors and windows which I do not want my little guy exposed to. So we're now using Ky-Ko Pest Prevention ###-###-####. They have several methods depending on what your house really needs, including a service to "seal" the home. I'm not using the home sealing because as long as they come out regularly we don't have a problem. I like them because they treated the inside of the house on the first visit, but only in the cracks & crevices so it was safe for kids and pets. Then they just do the outside every month or every other month.
Also, since our area (east mesa) seems to have a big scorpion problem, All of our neighbors get their homes treated - but each one of us uses a different company. We haven't compared notes this year to see who is happier with their service, but 4 out of 5 houses in our cul-de-sac have been treated in the last 7 days! I think the weather change has really made all the bugs come out, and the other bugs are the food source for scorpions.
Hope you get rid of them! They give me the creeps!
D.