The experience was great. Frank welcomed us with a proper description on how to use the facilities, and even about which were the nearby shops (there were many and that was really convenient) and what to see in Madrid. The location is great, very central so it can get quite "bohemian" and sometimes loud at night (at least now when it's summer) but nothing that will keep you up at night. I was with my aunt and grandmother and still, we didn't have to take the public transport at all. We walked everywhere! The flat was super clean and convenient, spacious bathroom and well equipped kitchen. Beds were not that comfy, but also not horrible. I'd definitely recommend it or book it again.