How should a guest perform the Bedikat Chametz on Passover?

What is the ruling for someone who is a guest at their parents' home and arrives on Thursday evening, the night of the 14th, before the stars come out?

If there is a private room where he stays, he should perform a kinyan with the parents by locking the door (the kinyan should be done after obtaining permission from the parents), and after the stars come out, he should perform the Bedikat Chametz in the room with a blessing. It is preferable that he hears the blessing from the parents. If he does not have a special room in the parents' house, he should appoint an agent to check the chametz in his own home, and even if he sells his house, he should leave one room that he does not sell in order to perform the inspection there. If he travels to the parents' house on Thursday after the stars come out, he must check the chametz in his own home, and even if he sells his apartment, he should leave one room that he does not sell, so he can fulfill the mitzvah of Bedikat Chametz there.