not number 9, but everything else sounds solid. the letter from a lawyer just might help a lot. a cam with saved footage should be a big help with the police and lawyer-- locks on coop, everyone should do, if you do call a sercuity co. it won't do any good if the coop not alarmed. I love your coop-- but I would do everything I could to re locate it. and plant fast growing shrubs with thorns in it's place.I posted a long time ago, giving the neighbors the benefit of the doubt. I'm sorry to hear this is still going on and that these people are obviously a special kind of insane. They sound like immature bullies. I don't suggest stooping to their level, but there are multiple things you can do to send them the message that their behavior won't be tolerated.
-- Move the chicken coop a few feet back from the property line if you are able to (to get away from the mothballs and also to force your neighbors to step over the property line if they want to mess with your chickens)
-- Tack up numerous NO TRESPASSING signs
-- Pick up a game cam or 2 to cover your coop and property line
-- buy locks for your coop if you don't have them already
-- Have a free consultation with a lawyer so you know your options (a simple 'cease and desist' letter for harassment sent from a legal office might scare the pants off them)
-- Call the police each and every time they violate the noise ordinance - find out how much money your neighbors should be getting fined for violating the noise ordinance and request that the cops actually enforce it next time.
-- Call home/property security businesses in your area and have them come out for a free consultation with you while your neighbors are home
-- If the cops refuse to enforce a law, and you are 100% sure there is nothing tying their hands from enforcing it, write your local paper
-- Go buy a gun and clean it in your front yard (ok maybe not this one)