Mouse in a Townhouse

[Justin Knighten]

A week ago a tenant notified me that she thought she had mice in her townhouse.  I suggested she put out traps and/or poison as pest control is her responsibility after the first 30 days (per the lease).  She doesn't want to do that because "they aren't safe for her cat" and "doesn't want a dead mouse in the walls".  A few days later she said she now thinks its squirrels in the attic...I went out to check the attic, because I certainly don't want a squirrel living in there.  No squirrel.  I could hear mice in the walls of her bedroom.  

My assumption is that most leases have the tenant take care of pests to discourage poor housekeeping.  This tenant isn't bad, and she does keep the house fairly clean.  I'm torn on holding the line and making her deal with it and having a pest control company go out on my dime.  I have no idea how these things are getting in, they are in a 2nd floor wall in a townhouse in the city, there aren't huge fields nearby.  I don't think it's caused by her poor housekeeping.  I do not know how clean the neighbors unit it (owner occupant, I've talked to him and he says he doesn't hear/have anything).  My fear is that they'll either tear the walls up themselves to deal with it (unlikely, she seems genuinely terrified of mice), or learn to live with it and I'll have 9 months of mouse damage to deal with at the end of the lease.  I know it's a business, and I don't want to train the tenant to cry about every issue and then cave on it, but I also know that if the roles were reversed, and it was me, I'd have a hard time handing over a few hundred dollars to "fix" something that isn't my problem.  

Anyone have and words of advice or creative solutions?