Would recommend Cristina's apartment. It is well located in a quiet, pretty street, about 10-15 minutes walk from the city centre, and with other bars and places to eat very close by. The flat itself was small but spotlessly clean, with a well-equipped kitchen with all that we needed to eat and cook basic meals (and make coffee!). There is a great view from the terrace above with a sun umbrella and sun loungers making it a comfortable place to relax and have a drink. Due to the style of the building the apartment doesn't have a lot of natural light so we preferred spending time on the roof terrace whenever we could.
The only downside for us was the temperature at night time. Obviously Seville is very hot during summer so we would leave the A/C on while we were out all day and close windows/blinds. When we returned, the temperature would be ok, but during the night the main bedroom was very hot, even with the A/C on. Maybe a second fan would be a good idea to keep the bedroom more comfortable.
Everything was very simple and easy in terms of checking in and accessing the apartment and although we didn't meet Cristina she was still a great host who replied immediately to several questions we had. Overall a great stay in Seville which is a wonderful city!