In my opinion there is only ONE method for removing mice successfully.
1.) Traps...snap traps, lots of them, like one every 10 feet in the attic along the walls or the kitchen.
2.) location and sealing of entry points.
If you do one OR the other, you won't solve your problem. Go to lowes or HD and get Victor traps, buy the whole box, they're cheap.
You can hire someone, but there is nothing they can do that you can't do yourself. You know your home better than they do and you know it doesn't take much of a hole for a mouse to get in...so start looking, low, high and in between.
[This message has been edited by jed1154 (edited 12/1/2010 11:41a).]