My stepdaughter allowed her boyfriend to move into her apartment about 1.5 years ago. He has been unemployed for 9 months and she has been supporting them both. The relationship is now over and he refuses to remove his things and move out. What can she legally do to get him and his belongings to vacate the property? (He is not listed on the apartment lease)

She has to go through the formal eviction process for her area. Check with the local housing court for what that process involves.

Agreed, she will have to give written notice and if he does not move do a formal written agreement