Luggage at Haneda - check in or store?

[jawsbad]

Will be arriving at Haneda early morning as doing a ship transfer from Yokahama.  Flight is not until 6:55 pm.  Plan to take the monorail into Tokyo for half day of siteseeing.  Flying United.  Can I check my luggage early in the day or will I have to rent lockers or use some other storage facility.

[BruceMuzz]

You will need to rent lockers - either at Haneda or at the Hamamatsu end of the Monorail.

If you leave the bags at Hamamatsu Station, you can easily collect them on the way back down to Yokohama after you tour Tokyo.