I would put some wooden stakes in the ground.
Wrap them with police line do not cross tape, I bet nobody would park their.
Or better yet, charge people to park on your yard.
Every house at Carlisle by the fairgrounds has parking for $10 a car.
Last day of the fair, I always pull out the police 'no parking' signs with the stakes. I probably have 30 or so now. I reinforce what they put up ever 5 feet or so. :)
