When I have gone out of town I have signed a "consent to treat" with my vet so they already know what to do if anyone comes in sick. (My guys are relatively young and pretty healthy so it is just me being paranoid.)

You should also see if he is a "door darter", i.e. does he run out the door the minute it is open.

How does he do with being alone for extended periods of time? i.e. will he pee on her bed