There's also a First Cabin property in HND T1 Domestic JAL terminal.
The rates are lower than Royal Park landside.
First Cabin is akin to capsule except the beds don't stack i.e. you have your own bedspace all the way to the ceiling.
Showers and toilets are shared, but very clean.
You will have to take a transfer bus there and back but the buses are very frequent - 10 min between headways.
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The biggest problem landing in Japan is you need three vaccinations - if you already have it, it's no problem.