Stick with the dash cam CB, they are proven to work even in a court of law, plus the bonus is you can run it during the day, whoever sneaks in at night, only knows they are there because they have seen them during daylight hours?
Set up a plant trap, get hold of a real "I want one of them plants" for free of course, and you know it will go that first night, just hunker down in the car and wait, still get it on dash cam, and hit ya car headlights, have ya car pointed right at the plant!....
Cheers BillyQ