I stayed here for some days. It's been a good experience. Even if it's the first time I booked a shared apartment, everything was not so bad.
The bathroom of the Studio, where I was, it's a little bit small... but I walked in the city all day long, so I just come back home just to sleep.
We were in three but you have to know well your mates, because there is the bed you see in the picture and a sofa, moreover we found an additional bed on the floor.
Good position as well, in 5/10 minutes you can take several lines (bus or metro).
Never seen the host but he wrote all the info by messages and he was always clear.
We have seen many people in the 5 days we were there, but I didn't see the room (or rooms, I don't know) upstairs.