What a fantastic place! Mikel was really nice and helpful to us. The apartment was perfectly located, two minutes by foot to Zurriola beach and ten minutes by foot to Parte Vieja (old town). Rent a surf board at Intersport near the beach. There is a bakery in the same block where you can go get your breakfast sweets :). (But you really don't have to because Mikel fills the fridge with yummy breakfast before you arrive...)
The apartment itself was newly renovated and the bedrooms were nice and big enough for 2 + 1 guests. Best of all was the terrace, with ocean view and also a view of Monte Ulia (well worth a walk! Go straight up from Zemoriya Kalea). We would definitely stay here again!