Karina and Andrea's apartment in Madrid is lovely. It's located a 10 minute walk from the Puerta del Sol. There are a lot of bars and restaurants within a 5 minute radius of the apartment. Even though it is close to many attractions and restaurants, it is very quiet. Me and my partner stayed at the apartment for 2 nights and it was the perfect place to explore Madrid. It is a little small, so for longer stays it might not be ideal.
I wanted to especially thank Karina and Andrea for their incredible communication! For recommending restaurants to us and for allowing us to check out later than advertised as we had a late train out of Madrid. I would definitely stay at Karina and Andrea's apartment again!