I tried staying at Narita airport. You had not better stay staying at Terminal 3.Becasue The Chairs are small and hard.and terminal 3 is very small.
I recommend you to stay at Terminal 2.
And mezzanine is recommended.There are many chairs and convenience store, yoshinoya etc.
Escalators going to the departure floor will be closed at midnight .
Yoshinoya on the 2nd floor and convenience store on the 1st floor are open 24 hours.
I didn’t see many people at Yoshinoya.
There are PC tables. You can take power. There is a place where you can take power at the sofa.
This is the Convenience store on the first floor. There is a sofa in front of the convenience store on the first floor. It is noisy to sleep here, so I do not recommend you to stay here.
There are many chairs on the second floor. There are also chairs that you can lie down so you can come early and secure a place.
It is ok if you put your”suitcase” to secure place.
There are also chairs on the first floor where is arrival floor, but the second floor is still recommended.
Please use it as your reference.