Originally Posted by
Finkface
You're welcome. I even found this pic so you know what it looks like. There is one 'regular' looking top loading machine tucked back in a corner (you can see it through the window to the right of the doors in the pic) that I don't think anyone uses that had a big sign on it not to use detergent. The big, main, front loaders had nowhere to put and no opportunity to use detergent. And, despite being able to buy absolutely everything from vending machines in Japan, laundry detergent was the exception which led me to believe the machines somehow did it automatically.
Here is the pic:

Thanks so much for attaching a picture. Your pic even shows that it's open 24 hours and I can definitely see the machine through the window. This will make it so much easier to find. Very grateful for your assistance.
I'll have to head over to the Westin Tokyo board to see if there's a coin laundry near there. Hope there's someone as helpful as you have been.
Happy holidays!