Great and beautiful place! I would recommend to everyone. It is in a perfect condition and is quiet because it is not on the street side. Also there are nice little details like lovely smelling soaps for every guest.
The only small pity is that the luggage storage provided by Sweet Inn is quite far away from the apartment, so if you need a place to store your luggage before checking in or after checking out, you need to drag your stuff quite a long way or store them in a locker at Gare du nord which is much closer.
Overall had a great time. Thank you!