We ( family with 13y old girl) spent 8 days in Marylebone. The flat really was wonderful and we find it very clean.
The location between Marylebone and Baker street station is ideal for exploring London by Underground or by bus.
The contact with Charlotte was very helpful and she answered very fast. We get several helpful tips for Shops an so on.
We would be happy to come again!!
Many thanks and I apologize for my English...
Ulrike