We had a fantastic stay in this apartment - it is big, comfortable, has all the amenities you could need (there's even a bucket and spade which our children loved on the beach) and as a bonus has a huge sun terrace complete with hammock! The location is perfect - a short walk to the beach, plenty of shops and restaurants in the vicinity, and a short walk to public transport (I recommend the tram for travel into the old town). It's also close enough to walk to the City of Arts and Sciences, with a lovely route via the Marina.
We loved Valencia and hope to visit again in a few years - and if Catherine's apartment was available, we'd definitely love to stay here again!