This was one my worst experiences with Airbnb.
The place is not in Gran Via, it's close.
The room which I was, it's beside the lady's bathroom, when someone took a shower during the night everyone in the dorm woke up because the walls are so thin, that looks like you are taking a shower too because of the loud noise of water.
Another problem is the shower, in the middle of the winter, during the morning the hostel didn't had hot water because it finished, so the guy that works there asked me to wait 20 min, I waited 30, the water was still cold, and he who wasn't carrying at all, asked me to wait more 40 minutes. I had a meeting, I couldn't wait anymore and I had to take a cold shower in the middle of the european winter (thanks for the unpleasant experience).
During my last night, I discovered that a relative passed way, so I went to the bathroom to cry, everyone was already sleeping. The employee saw on the cameras (I think) that it was taking too much time to me leave the bathrooms and went to check what I was doing, but in a very unpolite way, knocking really hard on the doors asking what I was doing. WHERE IS MY PRIVACY? IT WAS REALLY IN THE MIDDLE OF THE NIGHT, NO ONE WAS WAITING TO USE ONE THE TOILET.
This "lovely" place also doesn't have cabinets for you keep your belongings and luggages. Just a really small drawer that fit only two t-shirts and a trouser. Worst experience ever!