The benefit of a local guy doing it is you will most likely get the same guy every time...
That helps if he notices a problem area, he can focus on that for any future problems...
Sidebar:
When I moved into my house, the first day there a Terminex guy came by and started spraying.
I said, "Can I help you?"
Him: "I'm doing your pest control."
Me: "I just moved in, and haven't called anyone."
Him: "Well the previous owner had us out every month."
Me: (I know the previous owner) "Well, I'm not him, pack up your gear and leave please."
Him: "Well I already started."
Me: "Yeah? So? Am I supposed to pay you for services I didn't request, because if that's what you are expecting, you are going to be disappointed."
Him: "Fine."
And he storms away.
The previous owner had never dealt with them... They were just looking to make a new client.