Recently our rabbi gave a lecture from the Mishna Brurah concerning the obligation to divest oneself of ownership and possession of chametz during Pesach. The rabbi noted that if you accepted delivery of packages for your neighbor, then you have responsibility for the package as if you were the owner. A classic situation of a bailee. But with that responsiblity comes the issue of possibly owning chametz that might be contained in one of the boxes you accepted delivery for.
In our community, a member just opened a service that provides mailboxes to customers and helps them with mailing packages, as well. In theory, one of the packages he holds for a customer could contain chametz. Nevertheless, the owner of the service is not the owner of the package. How can the Jewish service provider release himself of responsibility for these packages during Pesach? Note: Decision of LOR is pending.