You know I wonder if this could be an issue with vacation rentals..someone keeps a remote etc. But yeah...its always a good idea to reprogram your garage door opener if its preinstalled. We've never had an issue in the past but we've installed our own door openers.
Pulling the cord while gone...smart
I don't know about houses down there but ours has a back door into the garage that we block with a huge toolchest and lock the wheels. Gonna make a person work for it if they break in
I think these people are pretty gutsy though because in a retirement community usually people are home during the days. Unlike areas where you see people exodus to work every morning.