We stayed at Juan's place for 2 days and I wish we had more time in Valencia. The house was handed to us in a perfect condition, it is such a smartly designed house - pictures do not do enough justice to the place and to the view from the window. It is well connected with both metro and bus, and seemed like a safe street to take a walk even at midnight. Juan had been a perfect host - it was raining the day we landed, he came to pick us up at the metro, he guided us through the house with no restrictions on usage of appliances. He offered us bikes to ride through the city (this could easily save you 10 euros a day by not booking a bike elsewhere). He also sent us a list of suggestions for sightseeing as well as eating out in and around Valencia. If you are in Valencia, then don't give a second thought before booking this place..I would not.
PS: If you read Spanish there is a treasure of books waiting to be read at Juan's place.