What's wrong with the cat?
she wouldnt lower herself into getting into a fight!
On the basis of what you've said I wouldn't call out the pest control just yet. I think Stuart is right, just the sight and perhaps smell of a cat is likely to be enough. You could bait a trap or 2 that can be cheaply purchased from hardware or DIY stores. It's also worth checking for and blocking any small gaps. Good luck but I wouldn't worry too much at this stage.
Nearly every year my cats get excited about certain areas of skirting board but only rarely do mice actually make an appearance. If they do, then the same cats act as a marvellous free pest control service, dealing with the problem pdq. I just think it is a fact of life in the Victorian houses of our locality. As long as you aren't seeing droppings I wouldn't worry.
I have the same problem at the moment.
Here is a website that might help
I prefer the peppermint as it is a deterrent rather than a killer!
other interestng sites that you might like , on different things...
these websites are really interesting, thank you for sharing them!