Maria’s apartment was excellent! The pictures do not do the view justice and the location is convenient to anything you want to do in the area (beach, pintxos, shopping). You can be on the sand in 5 minutes and in the old city in 10. Maria was extremely responsive throughout the process and offered plenty of suggestions. She even booked cabs for us as there is no Uber in San Sebastián. Would highly recommend.
Note, there’s some construction in the area on a neighboring apartment building and the nearby subway stop. This shouldn’t dissuade you from booking but something to be aware of if you are looking for total peace and quiet.