My wife and my two kids (13 and 8) stayed for three days in the apartment. It was a very good experience because everything was clean, comfortable, and easy. Despite being simple, it had charm and I felt it was very close to what an Airbnb should be.
If you are traveling during summer, I strongly recommend you take mosquito repellent. For guests with reduced mobility bare in mind that it is the penthouse in a 4-store building, so be prepared to climb stairs.