The first question I would ask is how long have you suspected the mice have been living in your house? If it has just been a few days, you could try to deal with it on your own. Set a few traps in the area where there is the most activity and see if you can catch the mice on your own. It’s at least worth a try.
However if it has been several weeks or more than a month, and you haven’t been successful in removing the mice from your home, it’s time to call in the professionals.