Abstract: Method, architecture and computer-readable medium to enable a user of a computer-implemented graphical user interface (GUI) to purchase air travel services. The method comprises receiving air travel parameters submitted via the GUI; receiving a selection made via the GUI, the selection being indicative of at least one selected service attribute from a service attribute set; determining a core price for a flight meeting said air travel parameters; determining at least one price differential associated with the at least one selected service attribute; determining a purchase price based on the core price and the at least one price differential; causing the purchase price to be displayed via the GUI; and causing said flight to be booked in response to receipt of a confirmation made via the GUI of an intent to purchase a ticket for said flight at the purchase price.