Daily Booking Calendar by Time of Day

I'm starting a transportation shuttle service and I want the passengers to have the ability to book their trip on-line via a webpage (I am using a Wordpress themed page with MySQL). I need an online booking calendar in PHP or other type where the passengers can choose between a one way or round trip. Then they would choose the date AND time of travel. If it's a round trip they would also need to choose their return date and time. The shuttle will operate every day and passengers will need to have the option of choosing from 8 different times of departure each day. SInce there are only a certain number of seats, the calendar would need to let the passenger know if a certain date/time slot is sold out. The passenger would then choose the appropriate fare(s) - child, adult, or special. The calendar payment would need to be integrated with PayPal. They would need to have the option of "Adding to cart" so they can purchase more than one fare at a time if needed. Here are the variables listed that we need: --limit choices to certain days of the week if needed --choose between one-way or Round trip. --choice of several travel times on each day to travel --choose from different fares (child, adult, special for each one-way or round trip) --ability to "add to cart" (purchase multiple fares) --ability to let the passenger know if a date/time slot is sold out --integrated with PayPal for payments