As with most retailers, especially a store whose square footage and the range of their departments is as large as Costco's stores, employees are expected to work around the clock, from early morning to late at night. According to employee reviews online, a newer hire is expected to have a more flexible schedule of five to eight hours a day and be willing to work a variety of shifts with varying days off. Other Costco employees say preference is awarded to employees with more seniority. Your interviewer may consider someone with an open schedule a more ideal candidate. Whatever your availability, evaluate your priorities and career goals, and answer honestly. Better to be clear at the onset to avoid burning out on the job quickly or giving them false expectations.