Originally Posted by
miklcct
If you use a hire car, you can drop it off in the city the night before and use the Airport Express to the airport in the morning. This may work out cheaper depends on how cheaper a city car rental is compared to an airport car rental.
With respect to which airports, is the city-airport bus/train/subway comparable in time and expense to shuttles from hotels that are close to the airport? HKG and HND (assuming the hotel is no further away than Shinagawa Stn) are the only two that come to my mind.