Rental car in Aso city

You're right. It looked quite very far from Kagoshima, even though it is an expressway.

It would cost I think 8000 JPY to do a one-way rental from Kumamoto pref. to Oita pref. apparently. Does not state anything if being returned in the same pref.

Wouldn't really drive from Kagoshima or Miyazaki, but rather from Noboeka.

I found there are apparently flights from Yakushima to Fukuoka as well. Only one flight though, ranging from 15200 JPY (to Kagoshima is from 9700 JPY).

Not sure if that would be a better option if visiting Aso from the Kumamoto side.

Fukuoka is out of the way for the route you wanna travel.

Oh, well yes, you're right. Didnt see Fukuoka was all the way up there =/

Say a bit curious, how is driving through Kumamoto city in the early morning (like 7-8 AM)?

The rental outlet was located close to the Kumamoto railway station west side (opening 7-20) and then another on the east side (8-20) and one near Kuhonjikosaten tram station, across the river from central Kumamoto (8-20).

I thought of perhaps the one near the tram station would be better, avoiding the hussle of the city, but that's only me.

In Nobeoka it is about 0,5 km SE of the railway station aparently. Not sure how navigating Nobeoka city is but perhaps easier than Kumamoto.

Both are easy enough to navigate by car. When in Kumamoto, the better option would be the east side one if you are unsure about driving.

Nobeoka is much smaller compared to Kumamoto. But getting to Nobeoka is a lot more work than getting to Kumamoto from Kagoshima.

Well, it is most that I am unsure of driving in Japan. I did drive once from Kagoshima actually but ended out on a quite a rural road (once the gps took me on a gravel road running through a rice field or something). I guess most drivers were kinda frustrated since I keep to the speed limit (so many that drove past me).

I would not fancy driving on motorways though as I find it quite intimidating even on our roads, at least getting on the motorway.

Still haven't decided on where to originate, as it would be interesting to see the east coast of Kyushu as well. And I don't really know how to come to Shikoku from Kyushu all the way from Kumamoto. A one way rental fee of several thousand is not something I fancy a lot.

Oh! you are still continuing to discuss...

This is my suggestions, if you still have a plan to reach Matsuyama and Shimanami Kaido:

-1 Driving is not recommended from Kagoshima to Kumamoto nor to Miyazaki, Nobeoka. It is boring.
So, take a highway bus at Kagoshima Chuo station, or at Kagoshima airport to Kumamoto.

-2 At Kumamoto, take a rental car.
[If you take a car by one way (Norisute) at Kumamoto and leave it at somewhere on the eastside of Kyusyu, you will need to pay extra 8.000 -10.000 yen approximately.]
-3 Visit first Aso region as much as possible.
-4 Next:
option 1: drive to Beppu by Yamanami highway (it's not an express way but a good driving road with nice views.) through Kuju, Yufuin etc.
option 2: drive to Takachiho gorge (and don't forget to visit Kunimigaoka hill where you can have a nice view over Takachiho town among the surrounding hills.
Drive down eastwards to Nobeoka by NR 218 (nice driving road), then to Usuki and Saiki (I recommend, in Usuki and Saiki regions, to leave NR 10 and drive as much as possible via seaside roads to Oita and Beppu (narrow and winding, but you can see and visit little fishing ports here and there.)
[Personally, I don't recommend so much Takachiho gorge (but visiting once would be worth it), much less so called Totoro bus stop (which has nothing to do with anime Totoro.]

Anyway...
-5 Overnight at Beppu.
-6 Take a ferry of 09:45 at Beppu port, and you will arrive at Yawatahama port at 12:30.
-7 To go to Matsuyama, take a taxi at Yawatahama port to Yawatahama station (JR Yosan Line), (1.2km). There is no appropriate direct express way bus to Matsuyama.
At Yawatahama station, take a JR Yosan Line train, that which starts at 13:27 (which comes from Uwajima) and you will arrive at JR Matsuyama station at 14:13.

-8 Take an express way bus to Onomichi or Fukuyama the day, or the next day. You can drive yourself if you like.

Wow. That's a great idea for itiniary. Thank you.

I looked at Google street view on the Totoro bus stop and unless it would be on the way to where I go I would rather skip it. It had some cardboard images of Totoro as it seemed.

But maybe it is worth paying the 8000-10000 JPY compared to going from Kumamoto to Shikoku the long way (10400 JPY for 150-180 minutes, Kumamoto to Beppu + 2460 from Yawatahama) (15180 JPY for 190 min Kumamoto to Onomichi...)

Hey, You can check the one way rental fee here.

https://rent.toyota.co.jp/eng/service/oneway.html

If dropping off in Beppu it will only be 5400 yen not 8000-10000. Maybe that makes it even more profitable to go one way OP?

Sorry, I don't understand what your calculation is.

But maybe it is worth paying the 8000-10000 JPY compared to going from Kumamoto to Shikoku the long way (10400 JPY for 150-180 minutes, Kumamoto to Beppu + 2460 from Yawatahama) (15180 JPY for 190 min Kumamoto to Onomichi...)


Anyway, one way surcharge is different depending on car rental companies. Toyota Rent A Car's surcharge is certainly cheaper than what I had a look at.
But, not all companies have their offices at same cities. Toyota seems to not have its office at Beppu. Beppu is not far from Oita, but in order to take a ferry in the morning at Beppu port, Oita seems to be less convenient.
And the most important is that returning a car in different island (Shikoku or Honsyu, in this case) costs much much higher.

I think that enough information has been given, the decision is already to be the OP's.

Wow, well I found out the oneway fee with Toyota from Kumamoto pref to Ehime would be 30000 JPY.... thats a bit much yeah....

I would have expected the fee to be higher from Kumamoto to Oita pref though. But I don't know how they actually handle one way rentals, if someone drives it all the way back or if it is used as one of their extra cars and a customer drives it back... Who knows.

I was thinking of staying in Takachiho for the night to see the dance show there but maybe it is not worth staying?

If leaving from Kumamoto around 8 in the morning, according to Google maps it would take (with the detour past the "broken" bridge that has yet not been added into the driving instructions) 1,5 hours to drive from central Kumamoto,

(and 15 minutes shorter if leaving from the other Toyota rental shop.)

Leaving by 8 it would possibly have me there by 10 at latest.

Google says around 45 minutes up and down from Mt Aso.

And adding some lunch, I would probably not leave Aso area until maybe 13-14.

Then it suggests around 70 minutes to Takachiho, arriving possibly 14.30-15.30 something.

Not sure when things start to close there but it feels like I wont get so much done there on that same day. Not that there is so much to see apparently.

A nice idea to go to Nobeoka thereafter and heading onward to Beppu.