The apartment (not really a penthouse as you might imagine, although it is on the top floor with 3 other apartments) is very centrally located and has a fantastic view. The communication with Unai worked wonderfully and was very pleasant.
Unfortunately we could not really enjoy our stay despite the great view.
Beside the disappointment about the size of the apartment (seemed much bigger on the numerous pictures) and the complicated check-in (could not find key box for a long time...) the windows were not sufficiently secured and could not be locked. So this apartment is definitely not for families with small children (like us).
Moreover, the apartment was very modern and very clean at first. However, one quickly noticed then that it is actually not really clean (bsw. sand on the floor; dishes very dirty) and with numerous defects (bsw. air conditioning is a pastel).
In summary: Unai's home is a centrally located studio with beautiful views but a clear case of overselling.