Landlord entry laws

[Mitchell Flaherty]

I recently closed on my first duplex. I inherited tenants, one of the tenants is fighting me tooth and nail every time I try to enter the unit for inspections and with contractors for quotes. He claims according to Wisconsin law I need to provide a certified mail 24 hour notice to enter. Everything I read states all I need to give him a 12 hour notice nothing states that it has to be certified mail written. He also claims that means that I illegally entered the garage because he has rights to the garage per his lease. His lease states that he gets half of the garage and the other tenant get the other half. I told him via text that I was entering the unit and garage days before I did. He has threatened me with legal action and has told me to go through his lawyer from now on. Does he have any grounds here? Everything I’m reading states that what he claims is all wrong. However obviously I want to double check.

Thanks for your time.