Superb location for exploring the old city of Valencia, the flat is neat and clean and has all amenities, with reliable Wi-Fi. Most historical sights are within walking distance, be sure to go up the Micalet bell tower 2euros, no need for a car. Lovely to walk along the old riverbed down to the port. Beautiful beach, plenty of cafes throughout the city to stop and enjoy the buzz in the plazas. Supermarket/bakery are within a very short walk, right opposite is a small shop where you can buy water and other essentials, however the Central Market is just round the corner for all your fresh fruit, veg, meat and fish.
Self check in very easy to use and communication once final payment made was very good. For eating out suggest you stick to Tapas bars, recommendations from Luis/Marisa were good, suggest you try to book on Friday/Saturday as they get very busy.