tenant rights with new owner

I am in the process of buying a duplex. both halves are currently rented out. once i close on it, i want to move into one side. the contract for that tenant doesnt end until june, though. Is there a law that says with a new owner, the contract is broke? what i want to know is when i can move in, if i have to wait till that tenant's current contract is up or if i, as the owner, would have the right to end the contract. i live in wisconsin, and am having a difficult time searching online for any law that explains this sort of issue.

[OHlandlord]

If the tenants in both sides of the duplex have leases, you must continue to honor those leases when you buy the duplex*. If the lease does not end until June, that tenant has the right to stay in the unit until June. You could ask for her to move out early, maybe offer some financial incentive to her, but she doesn't have to accept it. She can stay until June if she wishes. If she refuses your offer, notify her at least 60 days in advance that her lease will not be renewed and she needs to be out by the end of her lease.

Before you buy the place, be sure to get copies of both leases and read them well. Make sure you can live with all the clauses in those contracts, and be sure there isn't an automatic renewal clause or a clause that guarantees her the right to renew. You need to know this before you buy. You also need to make sure you get both tenants' deposits and any interest that is required to be paid on them by any state law at closing.

* There are some ways that you buy a property that does end a lease in some places. If you buy a property at a foreclosure sale or sheriff's tax auction, this ends the lease in some states. Be sure to consult your state law on this if you are buying the property this way.