Columbia's place is well located a short walk from the area's bars and restaurants and about a 10 min walk to the West end of La Concha beach and about 20/25 mins to the town. Her area is not touristy so you can get a feel for the local life in San Sebastian before diving into the busy areas.
She has a very nice apartment which you would share with her and maybe one other AirBnB couple or single person in the other room.
One bedroom has a balcony but she also has a decent size balcony where you will eat her delicious breakfast and look out across the bay - charming. Columbia is very welcoming and also gave us load of useful local tips, places to eat etc. Would definitely recommend. She also has parking (on request) but as we drive a pick-up truck it didn't fit but there is parking on the road outside her house and the area is safe. We only regret we could only do one night before moving on. Got to meet a great couple from Argentina too.