I know what you're going through. I had a similar issue until about 6 months ago when both of the neighbors kids moved out about the same time.
Video surveillance is a good start, but here's what I propose:
- Fabricate pepper spray to motion detectors for trouble areas in the yard
- Leave bait wired to 220v (please, take my shovel)
- Creative uses of
Funny Pranks with Liquid ASS. (super soaker by remote with video surveillance? Use with paintball gun? )
Just want to have fun with them?
duct tape their doors shut at 3am so they can't get out the next day.
More extreme, use hydraulic cement.
If they have a metal screen door - take an extension cord and cut off the female end. Strip the wires, attach to the door, and plug in the other end.
go to Sams club and buy 6 huge bags of economy size fruit loops.
wait until about 2 in the morning.
( Best before a big rain)
Dump and spread the fruit loops all over the yard. Let it rain then their grass will be about 8 different colors for about 3 months.
Remove the lock on their electric meter. They'll probably be suspected for tampering and get a fine. You could also roll it forward so they get a big bill.
Also, if you can get in their house when they go out... too many opportunities. Like installing an alarm in their attic with a remote.
spread poison ivy seeds in their yard
paint his front door pink in middle of night
use a pin, poke holes in eggs and leave in his yard to ferment. bonus points if you let them to stink first and get on his roof and drop down vents.
Other
If his mower is accessible, swipe the blade. JBweld their mailbox. Cancel his utilities (from pay phone). say you're him and going on a trip for a month. If you get into their car, place a heavy guage jumper wire from the horn to the brake switch behind the pedal. The result is honking every time they use the brake pedal. You might also get a bunch of bags of fertilizer (just the bags - lots), stash in his yard, and call homeland security.
Two final words - fecal attack.
You might start to keep the car in the garage.
Can you get a restraining order, even if its for kids?
Also, talk to a lawyer for options.
Don't abandon your castle.