Carmen is an incredible host. She is very warm and inviting and treats her guests like part of the family. I had a cold while I stayed with Carmen and she checked in on me often and brought me many cups of tea. Carmen's cats also took care of me! Her apartment is in a prime location near the train station (Atocha) and the subway is about a five minute walk away. El Parque Retiro is very close by and is definitely worth numerous trips. The wifi can be quite slow, but I had a data plan and wasn't too bothered by it. Everything is always very clean and the other guests are friendly too. Highly recommend for a short or long-term stay.