The present systems, devices, and methods relate to managing shared vehicle access. Authorization policies are stored at a network device, and are provided to vehicle devices. Authorization policies each include an authentication scheme, a list of permitted vehicle operations, and a list of requirements to perform vehicle operations. In this way, whether even if a user is authenticated to access a vehicle, vehicle access is controlled based one whether the user is permitted to perform vehicle operations, and whether requirements are met to perform vehicle operations. This provides a flexible and robust vehicle access system. Authorization Policies are distributed to vehicle device in an Access Configuration, which can be updated.