Yulia's flat is 10 minutes from the beach and only 10 minutes from the City of Arts and Sciences. The town of Valencia was only 30 minutes away by bus with regular (and cheap) buses.
The flat was clean and Yulia very kindly collected us from the tram station and drive us there when we were flying back home.
The flat is in a residential area with friendly locals.
If you're looking for a place to mix the locals and be near the beach I'd recommend Yulia's flat.