Yes, it is possible to extend a rental period after it has commenced. Getaround typically allows users to modify their existing reservations, including extending the duration of the rental. This can usually be done through the Getaround app or website, depending on the terms and conditions applicable to the specific rental. It is advisable to check the current availability of the vehicle for the extended time period you desire. If the vehicle is available, you should be able to finalize the extension easily. The total cost will be recalculated based on the new duration. For detailed steps or specific inquiries, users may find it helpful to refer to the appropriate section on the Getaround website.