OK, then for laundry (not dry cleaning), continue two blocks further down Seymour or Upper Berkeley Street towards Edgware to Seymour Place. Turn right and on your left, you'll come to a coin op laundry where they will take a reasonably large size bag of laundry, wash it and fold it for 12 pounds. It's ready typically in 3 hours or so and so far, they have always met the promised time for me.

Or you can do it yourself in the coin op machines for about 6-7 pounds.