From Haneda getting to the three properties by public transport involves a similar level of difficulty. Google Maps is good for directions but generally speaking here's how you would most likely want to go:
For Kanda: take the monorail to Hamamatsucho and change to the Yamanote Line bound for Tokyo. Kanda is the first stop after Tokyo.
For Shirakawa: take the monorail to Hamamatsucho and change to the Oedo subway line bound for Ryogoku. The stop you want is Kiyosumi-Shirakawa. Some trains terminate there IIRC.
For Nihonbashi: take the Keikyu train toward Shinagawa. Some trains run through to the Asakusa Line in which case you can ride straight to Higashi-Nihonbashi, just a few blocks from the hotel. Otherwise you will need to change trains at Shinagawa for the next one going in the same direction beyond Shinagawa.
In each case the fare is going to be around 600+ yen total and the door-to-door travel time around 40-50 minutes.