I have tried unsuccessfully to cancel my American Home Shield membership since June of 2012.
Once you call to cancel, they tell you a representative will contact you. They did the first time and left a message. Good luck with trying to return the call to that person or to the cancellation department.
I was told the last time that they saw the record of the request, but that I did not return the call to cancel (which I did). When my credit card was up for renewal, I just did not update it. I was surprised when my credit card company allowed the charges on the new card. I called them and got it canceled with a complaint about how long I had been trying to end this membership. They even sent a letter of dispute for me. Got yet another number to call on Monday... (naturally the office is only open for business during hours you want to call.)
Monetary Loss: $320.