The general rule is that travelers should use the most reasonable method of transportation given the circumstances. Please consider the cost of a shuttle service when compared to alternatives, such as taking a taxi or ride-share or driving a personal car and parking. Public transportation may or may not be a reasonable option when factoring the cost against convenience or travel time. Determining the most reasonable method of transportation is up to the traveler and the approver. If costs appear excessive or extravagant, the reimbursement request must include the business-related justification.