Diego and his family were great hosts. Contact was easy and responses prompt before and during the stay; check-in and check-out were straightforward; and they were great about checking in with me during the stay.
The room is very private. It's a unit in the attic of the apartment - while the apartment is accessible by elevator (I unfortunately don't remember if the entryway has any steps), you will need to head up a short flight of stairs to reach the rental unit from there.
I visited in August during the pandemic - as such, it was a quieter local vibe than might otherwise be the case. Having said that, Malasaña, Chueca, and Lavapiés are all under 20 minutes away by foot. Plaza Mayor is right next door. With that, and the short walk to Gran Vía and its (free!!!) 001 bus line, most folks will be more than happy with accessibility to sights and sounds in the city. Electric scooters are also plentiful, so do consider that as a method of transportation, if you're comfortable once you get a feel for the drivers you're sharing the road with.
The bed was comfortable, the AC was very effective, and the shower water pressure was lovely. Diego provided a number of packaged breakfast goodies - there's a toaster and I think? a tea kettle. I didn't inquire as to whether further food prep options were available, nor did I ask about clothes washing facilities.
Less than ten minutes' walk: my favorite place to eat was FOUR Café. Nobody asked, but there it is. Also, the small parks just south of the Cathedral (Google tells me they're the Jardines de la Cuesta de la Vega) are gorgeous, and the
Campo del Moro is likewise absolutely worth the time.
I highly recommend staying with Diego and his family!