have a good one

have a good one とはつまり「じゃまたね、さいなら」くらいの意味。0;40 have a good one. じゃ、またね。

https://www.youtube.com/watch?v=3VhPhHepY9I  0;59 have a good one. んじゃまた、ごきげんよう。
https://www.youtube.com/watch?v=FG-9Qa15ybQ  16:17 have a good one. じゃ、お大事にね。
Take Care, Mr. Elson: A Hard Road to Health Insurance | Times Documentaries | The New York Times

練習問題解答
a-1647 have a good one
b-6352 have a rough one