I had a DSC security system installed with cellular communicator by a Central Florida company. Besides the usual burglar detection I monitor AC fail (needed as I have a resi fridge), temperature (low limit) and water intrusion. This way when storing the coach I will get a call when any limits are exceeded. The security system has a pet friendly passive infrared motion detector. Depending on your coach layout and the size of your pet you may be able to use one as well even when occupied by your dog. So far my system has performed flawlessly for over two years. No issues with battery although I've not been without power for longer than 8 days.
2007 Allegro Bus 42 QRP, 400 ISL now 2017 LTV Serenity on a 2016 Sprinter chassis