There are a few households within range of my AM contour, and if I really wanted to increase the liklihood that one of them would find my station, I would put transmitters on every open frequency and literally hog the dial.
Of course people who ignore AM would be in their own culturally deprived world.
If possible, I might put an FM transmitter on a pole at the property line adjacent to their window.
If you like this idea and plan to do it join this thread and report your progress.