Highly highly recommend this place.
The host (Charo + Susana) are both very helpful and make check in/check out a breeze. They offered so many resources and support to make the stay extra special.
As for the place, it cannot be beat. Incredible views of La Concha, very clean, nice elevator, walkable to everything you are in San Sebastián for, has all needs for cooking and is just overall very charming.
The bed is great and they have blackout curtains as well.
I cannot recommend highly enough due to the combo of the wonderful hosts and place!