This place is really fantastic. Central location is about 10 minute walk from the nearest tube station, which takes you directly to the airport in about 15 minutes. There are several shops in the area besides the central market (which is literally around the corner). Note that at present, there are major road works happening on the corner and the noise can be tremendous during business hours - I only note this for those who may be looking for a place to work remotely, which I did but it was really disruptive - no fault of the owners at all, just unlucky timing for me. The works finish in the afternoon and the streets are pretty silent by midnight.
The apartment... totally my style with a mid-century modern vibe. A comfortable living room leads up two steps to an elevated, bright dining and lounging area which was excellent for working during the day. The dining room opens onto a really wonderful jungle terrace, which then opens directly into the bedroom. So you get lots of air flowing through the flat and it really feels open and bright with the high ceilings and circular floor plan. The bedroom is pretty big, and the rest of the flat is as expected for a Spanish flat. Kitchen is well equipped with almost everything you can think of. The owners provided a welcome basket of meats, bread and cheese and the fridge was stocked with cold wine and beers. There is a nespresso machine with a full supply of pods and sugar/sweeteners and there was a carton of milk in the fridge. So really, when I arrived there was not much to do other than relax.
The hosts are amazing. Communication up to the check-in was thorough and helpful, and Sandro phoned me upon arrival to check in and talk me through a few things.
So in summary, I would definitely recommend this place for anyone who wants a central location for exploring Valencia during a holiday.