I have pieces of non-legal advice.
#1 - ask the town to declare the road no parking.
#2 - read up on your town/city/county ordinances. You know when you pull into some businesses and they have signs listing a local towing company, non patrons towed blah blah blah? There's signage requirements.
#3 - based on number two, call around to some local towing outfits and ask them if they would like the exclusive right to send a half dozen trucks once a week and make those tows. They provide the signs, youll post em.see what they say.
#4 - Checking with the police at the local barracks/station. Ask what you need to post in order for an officer to be able to respond to the property and do a 'police ordered tow'
#5 - split rail fence at property line so they can't pull into yard
#6 - no trespassing signs at curb, spike strips hidden in grass.
#7 - have the police issue trespass notices to the owners of the respective cars each time one is on the property. It appears a second time, invoke penalties under law.
#8 - combine some versions of the above with purchase of parking boots and install the boot on the vehicle, after confirming legality with police dept for use on private property.
#9 - You said the people are 'not cool'..... invest in somethings that go Pew Pew and discuss your local castle doctrine rules, or lack thereof. because depending on what option you go with, altercations are near certain.
#10 - file police complaints, have reports taken of license numbers and numbers of cars, and have officers list which address the party is at. Multiple times of night to show how late. Not your statement, but their own observations. Then sue to have the st address declared a nuisance, include noise ordinance violations, refuse in yards, etc.
#11 - if you're not on septic literally flood your front yard for days ahead of time. Let them sink in up to the floorboards.