Javier's place is a great apartment right in the heart of Seville. You are literally steps away from the Cathedral and the Real Alcazar de Seville. It is very easy to see sights and return to the apartment as needed for relaxing. The view is AMAZING and I loved being able to open the doors to the balcony and just look at life happening.
There is a good amount of space in the apartment with a comfortable living room, good dining area and a kitchen with all the needs to cook. Extra bonus of having a washer and dryer. The bathroom is brand new and very nicely done. I was the only one staying at the apartment, and the bed is big enough for two, but moving around it might be difficult.
Only one note of consideration for the apartment - it is very noisy. This is not a problem during the day - if you are staying here it is because you want to be right in the middle of everything good to see. At night - and all through the night - it sounds a bit like you are sleeping on the street. I personally had no problem with it once I put in my earplugs. Just keep this in mind if you do not do well with noise.
Overall, a great apartment and wonderful host whom I would recommend to friends and family traveling to Seville.