This is a good location for exploring Madrid by foot! Lots of cool bars in the local neighbourhood too.
The room is clean and has storage which is great! The bed was pretty comfy, however there are some bars in the area so it can be a bit noisy on weekend nights (we were here for 5 nights).
The check in process is not ideal (limited time... But we checked in later), and having to message Charlie (there is no door bell and many levels). I had a Spanish sim, but otherwise I don't think the wifi was strong enough to use out the front of the house (it barely worked in the room for me which was frustrating).
It is like a hostel (two levels with at least 8 rooms). The bathrooms were clean but the apartment has an odd smell.
There is a kitchen on level 2 and we were able to access it when needed. It was pretty basic though. Has toaster, kettle etc though!
Overall a good place for the price in the city from what we found!