We stayed in Juan Luis's place for one month and found everything we needed. The location was brilliant, with a metro station a few seconds away taking you to a number of locations in Valencia. It was also within easy walking distance of the old town. There is a very big hypermarket (Carrefour) about a 10-minute walk away and lots of little restaurants and cafes nearby.
Regarding the apartment itself, the kitchen had everything we needed for our stay and we found it really useful to have a dishwasher. The air conditioning in the lounge was enough to cool the apartment down. The sofa and the beds were comfortable.
We did not meet Juan Luis himself but his friend Armi showed us around the apartment and gave us some great tips about the area and both Juan Luis and Armi were very quick to answer messages.
I would definitely recommend staying in Juan Luis's place.
Thanks!