When we bought our home in 1993 in San Diego County, it was a pretty down market and the house was on the market for a long time. The owners had bought another house and wanted to earn some money by renting this one. They rented it for some time and it didn’t work out well (he stopped paying and was evicted). When we moved in, after a week or so, I observed some large thrash bags stowed at the top in the garage filled with what appeared to be dry leaves. Further inspection revealed it was ‘grass’. I was a little scared and didn’t know what to do. Finally, I just tied it all up and disposed off in the trash. My wild guess is, it was atleast a few thousand $ street value.
Later on, our neighbor revealed that the “renter” was growing pot in the garage and also on the deck. The garage was wired up with pretty high grade (at least 20 amps) wiring, better than rest of the home!
For many years after we bought, we used to get letters (for the renter) from various police/sheriffs departments about impounds/seizures of cars etc., At first we were a little apprehensive, but nothing untoward ever happened.