Is it permissible to expand an apartment by annexing the area in front of its door, given that it does not impede passersby, and would this be considered falling under the warning of "whoever usurps a handspan of land"?

Common areas in residential buildings cannot be seized or treated as private property. Rather, they are to be utilized in a way that does not harm others or violate customs, laws, and ownership terms. These areas, bordered by the properties of others, are not exclusive, and every resident has the right to benefit from them as long as it does not cause harm to others. Therefore, it is not permissible to extend your doorstep into your apartment without the permission of the apartment owners and building management; otherwise, it would be an unlawful encroachment. As for the actions of the building caretaker, it is advisable to counsel him and report his conduct to his superiors, but this does not affect the ruling on the matter.