Do any of Marriott properties (hotels branded as Marriott, JW Marriott, Autograph Collection, Renaissance, or Edition) in London have laundry rooms with self-service coin-op (or complimentary) washers and dryers?

We're going to spend a week in London as part of a 3-week European Vacation. We don't want to bring enough luggage for 3 weeks of clothing.

I'm not looking for a laundry service or dry cleaning service. I've learned the hard way that when Marriott.com says "laundry on-site," it only means that the hotel's laundry service uses machines that are somewhere within the building rather than miles away. I've also learned the hard way that third party hotel booking sites cannot be trusted for laundry information.

Cost is not the primary factor (although hotel prices tend to be ridiculous).

We're looking for the ability to put our dirty clothes into a washer (and then into a dryer) ourselves, resulting in clean, dry clothes. We want our clothes to stay under our control. We want them washed and dried at temperatures we choose with the products we choose.

If anyone reading this thread has experience with self-service laundry at London Marriott-family hotels -- either success or disappointment -- I would appreciate replies.

Thank you!