We had a great experience staying at Laura and Lucia's apartment. It's a fairly big space and has a full kitchen and good working aircon (which you'll need in Valencia). The apartment is right in the shopping area and very close to the Colon metro stop. You can basically walk everywhere in the centre of Valencia or just rent a bike via the Valencia bike share system. The beach is a short metro ride away. The apartment has good high speed WiFi is on the 6th floor and has a doorman downstairs
The hosts provided a lot of restaurant and trip recommendations, all of which were excellent. They were also very helpful with all our questions throughout our stay.
I would recommend this apartment to everyone.