Moving to my parents - want to transfer service there, Xfinity is already there

I am moving to my parents house and I want to take my internet from here to there. My parents already have Xfinity at their home (it's under my wife's name - she runs the school in the basement there that has Xfinity). But Xfinity is giving me a hard time to move the service - I have to pay $100 for an installer to come. Again the service is already there, I just want to move mine to there and replace the existing.