When in the Message section, I often have the reflex to click on the thumbnail of the Inquiry to show the listing, but this does nothing. The "Show Listing" link is very small and hard to notice. I would suggest that clicking on the Inquiry thumbnail allows to go straight to the listing.
Also, when a reservation is made, I suggest adding a button "Show Listing" above the "Show Itinerary" and "Change Reservation" buttons, as this is the action a user would intend to fulfill the most frequently.
Thanks.