I stayed at Luis' place for 3 nights and I have to say I enjoyed it very much. When I pulled up in the taxi, I saw an old charming building, but inside, the apartment is gorgeous and modern. The apartment is 3.5 flights up, with no elevator, so be prepared to trek up your luggage. When I got inside the apartment, the first thing I did was go outside to see the balcony view. The view is amazing, with the Torre de Oro directly across the river. The balcony is pretty big, just like in the pictures. There is another section secured off behind the balcony, but that section also belongs to Luis, so it's very private. I didn't see any neighbors the whole time I was there. The lawn chairs are comfortable and there is plenty of room to dry out your laundry. Just a word of caution, when you go outside, don't make the mistake of leaving the lights on inside as I did. I had a problem with mosquitoes in the house (the place is right by the river, so there's bound to be a few mosquitoes around).
The apartment is very clean, with towels and soaps and amenities, and even though the Airbnb listing says that smokers are welcome, I didn't notice any smell that smokers had ever been there (and I am very sensitive to that issue). The kitchen has just enough for light cooking, but then who really wants to cook at home when you are in the middle of everything in Sevilla? The apartment is centrally located and is a short 10-15 minute walk to Los Remedios, where I went to the Feria de Sevilla. There are two large grocery stores about 3-4 minute walk from the apartment, so that was very convenient.
I would highly recommend this place. It's a great place for a couple on a honeymoon or someone who just wants to relax. I just wish I hadn't had so many things to do in Sevilla and could have enjoyed the place more. Luis was an excellent host, he was very quick to respond to any questions I had.