We stayed at Mercedes' place for three nights.
The apartment is located on the last floor of a three-story building. The stairs to reach the apartment are narrow but feasible for almost everybody.
There is a huge rooftop easily reachable, useful for hanging clothes and spend time outside.
The apartment feels much large than what shown in the pictures. Two people can stay comfortably, and for short stays I bet three or four can as well.
All appliances worked perfectly: the shower is large, hot water is precise and the small kitchen is equipped with a microwave oven, sink, fridge and gas other than a kettler. We didn't cook and didn't use the washer.
Everything was clean and tidy, the apartment is well organised and the bedroom is comfortable. The atico is exposed on two sides, which makes it fresh in the spring, even when it gets hot outside.
All in all, Mercedes was very reliable and also waited for us some extra time when our bus from the airport was late. The building is close to the Pilato house, just a ten minute walk from the Catedral and 15 minute walk from Santa Justa, the station where the bus from the airport arrives. A lot of bodeguas and bars are on Calle San Sebastian, a very very short distance away.
I would reccomend this apartment to everybody who wants to visit Sevilla.