We were staying at this accomodation during Madcool. First things first, this was one of three guest rooms in the apartment, plus thee host room. There is only one bathroom between the two shared guest rooms, but we did not encounter any major waits.
The accomodation was very well priced compared to all other accomodation available for our stay. This was a steal during our few days in Madrid. Secondly, this is a fantastic location. Right in the heart of Sol, it is easy to access from trains and the Madrid sights.
Our issues that stop this being five stars were hiccups with the hot water for the apartment. We went the first day of our stay with no hot water before finding out the boiler had to be reset (we had to then reset the boiler a couple of times during the stay). Secondly, there were minor issues with check in regarding the instructions to find the building, and our actual accessing of the apartment. This was sorted eventually however.
Overall we would recommend this place for a budget conscious traveller. You won’t beat this value for money as the apartment is very nice, functional, secure and has a kitchen fridge etc if you feel so desired for longer stays