You can buy all these tickets from the driver, with cash. Free travel for WDC elderly or disabled bus pass holders after 9am. .   travel in after 10am Mon-Fri, anytime Sat return anytime   up to 2 adults with up to 2 children travel in after 10am Mon-Fri, anytime Sat return anytime   travel in before 10am Mon-Fri return anytime   10 trip ticket (5 return journeys) use anytime   monthly ticket (unlimited use) use anytime   free travel for Chiltern Railways monthly or longer pass holders .