I had a very nice stay in the beautiful appartment. I felt very welcome. Marco was very helpful; he was my information desk. He also went on his motorbike to fetch my jacket I stupidly forgot in the bus. The appartment is in a nice neighbourhood, it overlooks a square.
I rented a bike that got me almost everywhere. I was allowed to take it into the metro without extra costs. People are not used to bikes so you have to take care. My stay in Bilbao was too short so I have to return again and hope to stay again with Olaia and Marco.