The best part about this apartment is the location! It's in the heart of old town and very convenient. The apartment is also big enough to fit 3 people (a double bed and a futon in the living room). It's clean. He also made available several guide books, one of which is super helpful.
When I first got there, I got a little lost. It's on a tiny tiny street off to the side that even many locals I asked did not know. Joaquin met me about 5 minutes after I arrived at the address and gave me a quick download of the city in Spanish, including a list of restaurants and flamenco shows in Triana. However, when I went to those venues in Triana, there weren't any flamenco shows and they opened later than he indicated. He was quick to respond when I experienced hot water and electricity problems and fixed them right away. He's very responsive. I was instructed to leave keys on the table on my way out.
Overall, if you are looking for location, sizeable space and a responsive host, this is a good option.