A friend of mine on another forum set up a motion sensor that turned on an audio recording of a gun cocking & a voice shouting at people to leave or get shot for when people trespassed. Not sure how he accomplished it.
Dummy cameras and signs saying there is video surveillance does work to deter thieves. My best friend was constantly having crackheads & people from the church next door trespass on his property to vandalize it, steal stuff off his porch, & try to break into his truck. We got him the dummy cameras along with the signs saying there was video surveillance & the vandalism & theft stopped.
Another thing is an outdoor security light that turns on via motion sensor. You can get solar powered ones or have hard-wired ones if you plan to keep your electricity on. Sometimes a light coming on or alarm going off will scare potential burglars off.
When you move in, you can get dogs that look scary. Or you could get a guard cow like I have. I no longer have scary looking dogs, but I have a cow with large horns who scares people off. One of her favorite games is chasing trespassers. She hops up & down & swings her horns around & scares the crap out of people. People from the power company made the mistake of snooping around my barn for no valid reason & learned to never do that again.