We really enjoyed Carla's apartment - it looks much better than in the pictures, it is really nicely designed, and it is well equipped (washing machine, microwave, cable TV, land-line phone, a safe and much more). Carla is a great host - super nice and considerate.
About the location: We stayed in Mexico city with two little kids. We planned to stay in one of the famous neighborhoods (Polanco, Condesa, etc.), but then we decided we wanted a place more suitable for little kids, and we found out about Napoles. And it turned out to be a lovely and lively neighborhood, with very few tourists and great atmosphere, many nice cafes and restaurants and a very nice park in the center.