Related Clues:

• Thanks to its being such a good buy, by the sound of it
• That sounds like a good buy, deserving gratitude at the double
• "Sayonara!"
• Conversation stopper
• Doubly thankful to hear this as one leaves?
• Exit line
• So long, and thanks, thanks again
• Goodbye to a vehicle maker
• Good-bye to All That, originally first part of autobiography
• Bye!
• Cheerio!
• Cheery send-off
• 'Later, bitches!'
• 'Bye for now'
• "Bye-bye," to a Brit