Location: can't beat it! Very short walks to the Cathedral, the Alcazar, and Santa Cruz to the south, Las Setas and lots of bars to the north, and plenty of fun stuff in Alfalfa too. Great food (eat at El Traga and get beers at Bar Alfafa!)
Apartment: Very clean, plenty of room, looks exactly like it does in the pictures. Central heating too. It was chilly so we turned the heat on and the apartment warmed up really quickly. I imagine the same would go for AC in the summer.
Host: Antonio was great and very organized. He met us right away and helped us book tickets to a flamenco show our first night. He also recommended we eat at El Traga, which turned out to be our favorite meal in Sevilla.