Su's place is amazing. It is in the center of the old town and very well located. It is a few steps from the Brextna Market. There is a cute wine store a few doors down. From the 6th floor patio you can see the river and one beach.
The apartment is not large but it is pretty and well appointed. It has a very nice shower. The larger bedroom opens up to the patio as does the livingroom.
Su was very helpful and made many suggestions and made restaurant reservations for us. She arranged to have us picked up at the airport and this gentleman also took us to the apartment. I would highly recommend this location if you are staying in San Sebastian/Donostia.