This apartment is absolutely great. It is stylishly decorated, it is spacious, enough for 2-4 people to fit very comfortably. It has an amazing view from the deck, and is literally two blocks from the beach. It is located in a great neighborhood in San Sebastian, the Gros neighborhood, and is just a short walk from Old Town. It is literally close to everything you'd need.
The apartment isn't the only thing that is great. Mikel is the best host I've ever met. He's friendly, he responds very quickly and gave us so many tips as far as places to go, how to get there, etc... He's a super nice guy and easy to talk to.