Overall we were satisfied with our stay! The apartment was clean, well equipped and very close to basically any kind of public transportation, which was great.
Communication with Catherine went smoothly, she was always quick to respond and very informative.
As deep country people, who aren't used to a lot of city noises, we felt it was a bit loud. You could always hear cars or the tram passing by, which was a bit annoying - especially at night, but that's to be expected as the apartment is located in a busy part of the city.
Nevertheless we highly recommend staying with Catherine if you're planning to visit Brussels. We had a lovely time with a lot of great food and lots of adventurous activities.