The apartment is in a great location, very close to most bars, restaurants and walking distance to the downtown. As for most of central places, it's a busy noisy during the whole... but this is a price we pay for being so central. If you are looking for a quietness, maybe this one is not for you.
The hosts were very kind in providing very detailed instructions and guidance on places to visit and eat in the city. If you are going by car, the also provide a private parking which is in a garage 5-min from the apartment. My only advice is to avoid arriving at peak hours... find a parking space for the check-in was very problematic (I suspect I got a fine while I stopped the car to unload our luggage... let's see).
Although our stay was very short, we enjoyed the city a lot and now we regret haven't booked one or two additional days... Bilbao and the Iñaki and Ianara's place worth every penny.