Oh yeah I forget vehicles......
Yeah sugar in gas tank is obvious and shit once they get in, and insurance is liable to even cover most of what seems like a terrible thing to happen to a car. But that is triad and true revenge. Although that is taking an entire vehicle out of commission.
There are various things you can do to paint jobs of vehicles with acids and other things......many....many things. Those aren't expensive to fix, and you could do just a few spots on a few panels to make the car fucked all over. Once again insurance might get to flip the bill.
Slashing tires is a good idea and new tires cost like $400 or so depending on what you are working with and there is a good chance the family / she would not want to make an insurance claim against something for such a small amount, especially when the deductible would be like $250-500.
Heres an idea I never thought of.....find a super abrasive stuff.......Like broken glass or metal shavings or something.......this is a PURE GUESS, but I bet if you put those on her windshield wiper on a rainy day, when she hit the wipers you could hope for it to fuck the windshield up.
Plant drugs on her. Like some crack, give her enough for a felony charge. She'll never forget that, and you would ruin her life.
Although you shouldn't really do much here, honestly everything I've said is illegal, and liable to end up with multiple misdemeanors and felonies. Most of these things could be traced right back to you unless you are a pro at not being around when her shit gets fucked up (and she doesn't connect the dots.....or go on newschoolers.com)
You yourself could wind up wishin you would have taken your dakine to a sewing shop and had them stitch it up like a pro for $20.
Or even just sending it to Dakine and trying to explain your situation (as unlikely as the circumstances sound).
I would take the high road here, the low one will only up the ante, and ask for trouble with most likely the police. And they are no fun to have hatin on you.
The only way to get even is to not get caught, and right now especially anything that "oddly fucks up on her" she will think of you. But say...3 months...7 months down the road. She will never suspect anything...yeah it would take a while to get your satisfaction. But now is the wrong time to make any serious illegal moves.
/ DA LOWYA