We (3 people) had a good time at the apartment. In contrast to most airbnb "hosts" who are just professional rental agencies, Natalia's place is actually her apartment where she lives. The apartment is clean and the view from the balcony is great, as in the photos.
However, I would definitely not recommend staying with more than 2 people. The mattress in the living room is only a few cm thick and is quite uncomfortable just lying on the hardwood floor. Also, the apartment is in a 1960s style building in a somewhat run-down part of Lausanne that can only be described as "little Africa".