[Suggestion]
Day 1
: Arrival into Narita Airport [NRT].
: Heading to Tokyo.
Day 2
: Heading to Nikko mainly by the Tobu Railway lines.
Day 4
: Heading back to Tokyo.
Day 5
: Heading to Kawaguchiko mainly by expressway bus.
Day 7
: Going to Mishima Station by expressway bus.
: Heading to Kyoto by the JR Tokaido Shinkansen.
Day 9
: Making a round trip to Nara.
Day 10
: Heading to Osaka.
: Departure from Kansai Airport [KIX].
Expressway bus reservation
(a) Shinjuku Expressway Bus Terminal -- Kawaguchiko Sta.
https://www.highwaybus.com/gp/inbound/inbPlanList?lineId=110(b) Kawaguchiko Sta. -- Mishima Sta.
https://japanbusonline.com/en/CourseSearch/12200050001Busta Shinjuku (Expressway Bus Terminal)
http://shinjuku-busterminal.co.jp/en/
Tobu Nikko Pass all area
http://www.tobu.co.jp/foreign/en/pass/all.htmlJR East Travel Service Centers in Narita Airport
https://www.jreast.co.jp/e/customer_support/service_center.html: Here you can purchase JR tickets for your Shinkansen train ride.
[Comments]
It is not recommendable
to drive a car with little kids for tourist spots:
you may get caught in a traffic jam,
making your kids feel boring and tired.
Also,
your detour from Kawaguchiko back to Tokyo
(just to return your car)
results in paying more for your car and Shinkansen train rides.
[Simulation of costs]
For one adult, one 3-year-old kid and one 5-year-old kid
to get from Tokyo each to Nikko and to Kawaguchiko then to Kyoto:
Note
: As long as the above kid is accompanied by the adult,
except when he/she has
a train seat which can be reserved or a designated bus seat,
he/she can travel free from railway and bus fees.
You travel as you now plan:
- Expenses on driving a rental car
(= car rental fee + gasoline charge + expressway tolls)
for your three listed routes
: Probably at least 40000 yen.
- Tobu Nikko Bus fares
: At least 2100 yen.
- JR basic fare and Shinkansen surcharge
for the adult to go without seat reservation
from Tokyo or Shinagawa to Kyoto
: 13320 yen
- Total
: At least 55420 yen.
You travel as is suggested:
- Railway fares
for the adult to get to Asakusa and back
: Up to 800 yen.
- Tobu Nikko Pass all area for the adult
(covering Tobu Nikko bus rides)
: Up to 4600 yen (depending on seasons).
- Railway fares
for the adult to get to Shinjuku
: Up to 400 yen.
- Expressway bus fares for the adult and kids
to get to Kawaguchiko Station
: 4000 yen.
- Expressway bus fares for the adult and kids
to get to Mishima Station
: 4600 yen.
- JR basic fare and Shinkansen surcharge
for the adult to go without seat reservation
from Mishima to Kyoto
: 10780 yen
- Total
: Up to 25180 yen.