Where to start.
Aside from the amazing flat with a great vue on the Llotja de la Seda, Juan himself was incredibly hospitable, giving us tips and insight on local history. His golden personality alone should make you want to stay at his place, but more concretely the flat is in the historic center, so great location. You can easily walk around the center and to El Carmen, take a stroll in the jardin de turia and explore the city.
I highly recommend and would love to go back myself soon.