We had a lovely stay in Sevilla at Cristina's appartement. The place is well-equipped and clean. It is also well-located to easily access the city center but it is very hard to park around if you have a car (the area is free but spots are rare! you may try your luck in the nearby streets or Calle Torneo or eventually Camino de los Descubrimentos)
Cristina is very reactive and helpful, the toilets were not working properly and she tried to fix it quickly. A little downside is that there are dogs in the building that sometimes can be noisy at nights.
We could not fill the book for the best adresses in town but we recommend Bar Alfalfa and Bolas' ice creams!