Our experience was great. Thanks to Mario, Melvin y Renan. They were great hosts. Communication with them was super easy. They were in contact with us a couple of days before we got to the apartment making sure we got there safe and making sure we didn't get lost. If we needed anything they were there to help us in less than 10-15 mins.
The apartment is just like in the pictures. For some people it might be small, especially if it's four adults staying there, but it worked out perfect for us. My wife and I stayed in the room and our two teenage girls stayed in the futon. The apt was clean and we had everything we needed. From pots and pans to toaster, coffee maker etc. Having the stove was a plus, because we cooked breakfast every morning. There's a small shop around the corner that you can buy snacks, drinks, bread, eggs etc. Just a reminder...in Europe the water heaters are small so you have to take quick showers especially if there's 4 people staying (it wasn't an issue for us). The Wifi worked great, it was fast and reliable. The AC, even though we didn't use it much because it's winter, it worked. There are three separate heater units that worked very well also.
The only thing about the apartment is that the walls are very thin, if you have a neighbor that is not considerate and makes too much noise it might be an issue for you. Our neighbors were getting a little loud and we talked to them and problem solved.
Don't forget to bring your own toiletries.
The best part of the apt was the location. If you notice in the pictures you can see a metro station, it is literally across the street, just a couple of meters away. There are plenty of restaurants and shops around. Everything is within walking distance. We walked from the apt to Plaza España, Puerta del Sol, Plaza Mayor, Templo Debod, Palacio Real, we walked the entire Gran Via and Calle Mayor. We even walked from Parque del Retiro to the apt. From Retiro to the apt was less than 2 miles (3 km).
We are really happy that we stayed there. Thanks Renan, Melvin and Mario for making our trip to Madrid an unforgettable experience. When we come back we will try to stay here again if it's available. Muchas Gracias por todo!