Checking Chametz in a Shelter

I am looking for a halachic solution lechatchila. According to Halacha, a communal shelter for all the building's residents, where chametz is brought in, must be cleaned and checked for chametz, or it should be rented to a non-Jew with the consent of all the residents living in that shared residential building, as a partner cannot rent out his part without the consent of all partners. If it is not possible to remove the chametz of the neighbors, such as during wartime, and since these neighbors currently do not observe Torah and mitzvot, and it is also not possible to rent the shelter to a non-Jew without their consent, and even if he renounces his part before three, it seemingly does not help to exempt from checking chametz, since the place where the chametz is located is also in his possession, and although he does not violate the prohibition of owning chametz because it is not his, nevertheless, he has an obligation to check, just like any chametz found in his house, which, although declared ownerless by saying 'kol chamira', still requires checking. So what can be done according to Halacha?

Shalom Rav,

The way is by renouncing your part before three people.

There is no similarity between renouncing chametz that is in his possession, where there is still a concern he might come to eat it, and renouncing his part in the area, which causes the chametz not to be in his possession.