Landlord rights?- selling while rental property is occupied

[Nikki Eilefson]

I am trying to sell the condo I own while it is occupied by a renter. The renter is very unorganized and leaves the place a total mess while showings are going on. Overall, the place is not "dirty", he just seems like a packrat and leaves stuff all over the place. What kind of rights do I have as a landlord to ask him to straighten up the place? I have asked him to tidy up, but he is very stubborn. Meanwhile, it is being shown to potential buyers who are leaving completely uninterested.