Living in Minnesota it is guaranteed to get cold while we snowbird. I turn off the water just in case, turn the heat down to 50, lock up and go.
But, I pay a neighbor to clear the snow and they have a key. I also have a reasonably priced Freeze Alarm that has three phone numbers programed into it that it will call and give a message to them should the power go out for more than an hour or if the temp gets below my preset temp. It will call the neighbor, my son who lives in town and my wife's cell phone. If I call the house, hang up and call again, it will answer and tell me the status of everything and I can change any of it's settings. If I don't do the call back thing, I'll get my voice mail so I can check on that too.
http://www.amazon.com/Control-Products-FA-I-CCA-Intermediate-FreezeAlarm/dp/B000071NYC