We stayed at Julian's place for 2 weeks. Check in was easy and Julian was kind enough to let us check in early since our flight arrived in the morning and the apartment was not rented the night before. This apartment is in a great location, within walking distance to everything you may need as well as many tourist attractions, but also easy to get anywhere in Madrid with a metro stop and bus stops right there if you don't want to walk or the weather is bad. It's on a busy street but the apartment faces the back of the building so it's very quiet - we had no noise issues at all. Everything in the apartment was exactly as described in the listing and shown in the photos.
A few positive things that may not be highlighted in the listing: The bathroom and bedroom have great storage so you can put away your things and not live directly out of your suitcases. The shower is exceptional and the bed very comfortable. The building has 24-hour doormen - so even though we never felt unsafe in the neighborhood, there is an added layer of security knowing that someone is always present in the building.