Buy JR Pass if in Japan if for 3 days?

Hi all,

My friends and I will be staying for 3 nights in Tokyo and then travel from Tokyo to Hakata (Port) on our last day to catch a ferry to Busan. We have three plans:

1) Buy the JR 7-Day pass and use it to travel around Tokyo and for the train ride to Hakata. We checked on hyperdia and train ride from Tokyo to Hakata was around 21000 Yen, so we don't know if the costs might add up if we travel within Tokyo itself and to Hakata.

2) Don't buy the JR Pass, buy whatever pass to travel around Tokyo and then take Skymark Airlines to Fukuoka to get to Hakata. Last time we checked, the flight rate was around USD150 per person from Tokyo to Fukuoka.

3) Don't buy the JR Pass, buy whatever pass to travel around Tokyo and then take the night bus (14hours) to Fukuoka to get to Hakata which costs 15000 Yen.

So, any recommendations which plan is better? Also, what pass do you think is better to buy to get around Tokyo if we don't purchase the JR Pass?

I'm sort of new to all these and would appreciate very much for any kind of suggestion. Thank you!

I personally would fly with Skymark. How about a direct flight from Tokyo to Busan? It might be the cheapest overall option.