The apartment is not very spacious, but organized so cunning, that up to 4 people can comfortably stay there. The sitting room is fully separated from the kitchen and can serve as a sleeping room. The child’s room is decorated with toys and books for a child of 3-5 years old.
The apartment is very cozy and perfectly equipped. We have found there not only kitchen appliances, laundry and towels (which we expected), but also shampoos, shower gels, household chemicals, sunscreen cream, salt, pepper, different seasonings and so on. That was especially useful as Iberia lost one of our bags and found it only next day.
The host, Vincente met us in the apartment and presented with beer, snacks, milk. That was really great after 10-hour flight as we very hungry and too tired for immediate shopping. Thanks a lot!
And Vincente speaks perfect English! 
And a small life hack:
It takes 15 min walk to get to the nearest metro station, 15 min walk to the city center and 30 min by bus to the beach. Using metro to get to the beach is much longer and less comfortable. On the very first day we invested 40 euro into metro-ticket, planning to use it every day, but that was absolutely useless.
But renting a bicycle would be the best way – Valencia is the best city for bike-riding!