We stayed at NH Marseille Collection hotel from 1st October till this morning (reservation number on booking.com 2840547623).el.
On the night of our arrival, right after we checked in our room, I opened the window (which I later found out was supposed to be blocked, but was not) in order to close the window shutter. As soon as I touched it it lost balance and was about to fall down in the street. I managed to keep it up (at my own risk) and pulled it inside the room. It was clearly never been attached to the wall (as there were no holes and no screws in the wall) and always been just leaning on it. That was very dangerous for me while grabbing it and also could have seriously injured people walking in the street! You can immagine how surprised I was! I then called the reception and they sent a person to the room who just grabbed the shutter and took it away. Nobody even offered to replace our room.
After a while we found out there was a big red spot on the mattress, clearly visible under the sheet. We called again the reception. They told us to go downstairs to get another room key and they 'sent' us to another room.
We reached the other room and moved our baggage by ourself. The room was smaller and not as nice, but ok. However, as soon and we pulled down the bed sheets we found out, again, they were dirty with blood (as there was a clear red spot on the top sheet).
We called the reception for the third time and got another room. This time the bed was clean, but there was a sigarette butt on the windowsill. The whole thing took more than 1,5 hrs and we were tired so we decided to keep the room with the cigarette but without calling the reception again.
This is DEFINETELY NOT what you expect from 4 stars 'collection' hotel.
NOT RECOMMENDED