We had a great stay at Carolina's 7th floor apartment overlooking Zurriola Beach! It was very centrally located to basically all of San Sebastian (old town is a 10-15 minute walk) and it is located right in the middle of the Gros Neighborhood where there are tons of panaderías and shopping. On a sunny day, I highly recommend the Monte Igueldo Funicular Railway to the top of Monte Igueldo where you can have a panoramic view and a drink or hot chocolate at the hotel up there. (side note, funicular is only open certain days of the week and in certain seasons). I also highly recommend making lunch reservations at Pollitena and dinner reservations at the Michelin start restaurant Bodegón Alejandro. I really enjoyed the clothing boutique called Pas Si Simple. We had rainy weather most of the time, so we mostly just ate pinxtos and walked around and enjoyed the city.
*Parking: can be tricky- there are 3 parking garages nearby, we found that the Parking TXOFRE was the cheapest if staying for a few days (15 euros a days instead of 25 at the others). Park your car in one of the spots labeled "Público" and then walk to the center office where is there a person who you can pay upfront for the amount of days youre staying. He gives you a ticket and then you use that to enter and exit the garage each day.