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Might be a good time to paint the interior of the home. You might want to hire some guys that like to play really loud music while they paint, use bright lights, paint 24 hrs a day until the job gets done, etc. Of course by all means confer with your attorney before you take any legal actions.
We have are share here in Detroit you best solution would be to go there knock on the door try to get a hold of them in person. Offer them money for them to leave, once they come to an agreement have them pack their stuff and be there physically when they are leaving, at the same time replace all locks on the doors. A lot of people will tell you to talk with an attorney but this can be handled with out one besides by the time you done talking with an attorney and have him do their services it will cost you more then just talking with them in person. I have an advantage my neighbor is a police officer and actually accompanies with me to the property this makes the squatters get their full attention. But that’s my advantage maybe you have a friend or family member that is an officer and may help, all they need to do is be there. I usually get the “I don’t have anywhere to go” answer and “what you are doing is against the law” and blah blah blah, in the end I give them the choice either take the money and show them the cash or it will be a matter of time until courts approve and you and the rest of your belongs will be on the curb. Also make it firm that if a resolution doesn’t happen right there right now, the offer will not be available afterwards. I usually have squatters out for $200 to $300. And usually out the same day.