Sony is a great host. The check-in and check-out was easy and whenever we had questions she responded very quickly.
We could perfectly use the terrace on the rooftop for breakfast or a barbecue. The flat is very comfortable with enough space and equipment.
The walls are quite thin, so it can get a bit cold in the evening. But if you turn on the heating early enough that shouldn't be a problem.
To get into the city centre you simply take the metro or the bikes that you can find everywhere in Valencia. Both doesn't take long.