Me and GF depart Narita T1 on a 09:15 flight, so need to be there at 07:00 for check-in. We are staying at Mitsui Garden Hotel Otemachi which is about 15 minutes walk to Tokyo station. The only suitable Narita Express train is the 06:18, which arrives at NRT T1 station at 07:18. And the price is JPY3,020 (~GBP21) each.
It might bet better to get a taxi? On Sunday mornings the roads should be quiet. How much would it cost? How long would it take? I could ask the hotel reception on the Saturday evening to reserve a taxi for the Sunday morning.
Thanks
I had a very similar itinerary before. You should be fine with Narita Express or Keisei if you're willing to do the transfers. If its your first time leaving from Tokyo Station, arrive early in case you need additional time. On my first time leaving from Tokyo Station, I came very close to missing the Narita Express due to issues with the ticketing machine and finding the correct platform.