Sadly, local TV stations usually do not have much of a creative department. They are ad salesmen, they are trained to get the time slots filled. The ad message and content are after thoughts so, if you don't supply your own ad then you are at the mercy of their routine panning and monotone dialogue as they display your business. "Show the truck, show the house, show the workers working etc. etc.
Hiring an ad or marketing agency can be expensive. You could hit up the local college videography, photography department and run an ad contest. Give the winner $500 or donate something the department needs.
Here is a free idea for you that I threw together.
Have your ad be completely silent. Why? Because the TV is "Always talking" it never shuts up. If the ad is silent people will look up, or walk back into the room to investigate why their TV is quiet. Anyway, here is the sample idea: