Let us say a person lives in an apartment building where the apartment doors (door to the apartment itself) are fitted with electronic locks. The building has a 24-hour "concierge" doorman (non-Jewish).
What sort of interaction could a Jew have with the doorman at any time in order to allow themselves to enter their apartment on Shabbos?
(Assume the lock cannot be changed, assume stairwells exist so elevator is not also issue. For the purposes of this question, assume you cannot get a roommate to help you.)