Staying at Luisa's place was a high-quality experience. After receiving a timely welcome from her father-in-law who lives on the same floor, I found the accommodations to be extraordinarily clean and tidy. Seriously, this is one of the cleanest apartments I've ever been in. The bedroom's window grate blocks out light very well. The bathroom is nearly as big as the bedroom; take note that it's located separately down the hall. Fast wifi and easy access to the building.
Any drawbacks are no fault of Luisa. The walls are quite thin so you can hear what's going on with neighbors. Although safe and near key transit hubs, the location isn't so close to many of Madrid's main attractions—perhaps that's a good thing to get away from the bustle, but prepare to walk or head to the nearby metro station.
I only met Luisa briefly, but her communication through the app was friendly and reliable. Altogether a very easy place to recommend. Thanks, Luisa!