My wife and I spent two nights in Bilbao, and our experience with Oscar made us regret we hadn't planned more time there. First, the apartment was wonderful - homey, stylish, and well-appointed. Our room was cozy, with a comfortable bed and plenty of space for our belongings. The living room, the main shared space, was outfitted with a huge couch, dining table, and (my favorite) a stuffed chair and ottoman - a perfect space for relaxing after a long day of art and food, as well as catching up on a little work from home. The apartment also has 1 and 1/2 bathrooms (a major plu), and a nice little kitchen. In terms of location, it is steps from the food and fun of the Casco Viejo, as well as the tram that will take you to the Guggenheim and other points of interest.
All that said, the biggest selling point for the apartment is Oscar himself. His hospitality, help, and enthusiastic attention to our needs made the trip. He was quick to respond to messages, and always gave us extremely useful tips and information. Upon our arrival, he provided us with recommendations for restaurants and sights to see that were gold - take my advice, take HIS advice. Whether you are interested in pintxos or finer dining, he knows all of the best places, and is happy to help with reservations. We look forward to returning to Bilbao soon, seeing our new friend Oscar, and staying at his charming apartment. I can't recommend it more highly.