We stayed at Mario's apartment for 3 nights. The best part of this apartment is the location. Everything is really close on foot. The apartment looks like the photos, small, cozy, with hot water, but with windows that hardly open. What you can not see is that the door has no lock, just a key that opens the door (but the building has outside a keyboard system to enter inside; Still we were a bit worried). A better locking system would be great.The second thing you didn't see is that, because the apartment is in a central location, there is a lot of noise.
Lastly, about Mario, we didn't met him, but he responded direct in our messages. He left us the keys on the apartment's door, because we arrived late(so we weren't sure, if we would find the keys). The last one is that we wanted to leave our backpacks somewhere safe, but the only place Mario suggest us was the first door you see when you enter the building, which is unlocked. So again we worried about our things. Mario tried to respond to our demand, but it was unsuccessfull.
Though the problems, I recommend Mario's apartment mostly for few days.