The below link might be of interest to you.

https://www.youtube.com/watch?v=vIapoWBZAGg

Happy Travels!

I asked about travel dates because when in April matters. You will probably be early for cherry blossoms. I think your best bet for that would be in Tokyo at the end of your trip. You'll want a couple of days in Tokyo simply to have a better chance of a day with good weather.

Which hotel in Shinagawa? Some hotels are across the street from the station and others are a few blocks up a hill.

I booked a room at the Marriott (since I'm a gold member, we will have access to the lounge) which is a 10 min walk up the hill from Shingawa station,and I booked a room at the Citadines Shinjuku. I'll cancel one of them before we leave.

ok, good that you are aware that it is up the hill. If status benefits interest you then you could consider Starwood properties. Did you get the status match?
http://www.marriott.com/marriott-rew...my-accounts.mi