This is a fantastic apartment and I really enjoyed my time there. I stayed for 3 weeks with my husband and a friend who were both looking after me while I recovered from surgery. I didn't leave the apartment very much at all (on doctor's orders), so having such a wonderful place to stay was a real blessing. If I come back to Madrid I will definitely be staying here again.
The location is very good, with a metro station just a minute's walk from the front door. Everywhere we wanted to go was 40 minutes or less on the metro, which is quicker than taking the car when you factor in how long it takes to find a parking space in Madrid! Speaking of parking, it was not always available directly outside the apartment, but we never had to walk more than five minutes from the car to the door.
There are quite a few restaurants and bars nearby which were friendly, and there's also lots of smaller shops nearby as well as an Aldi and a Mercadona a five minute walk away for groceries.
The apartment itself is a good size, with two bedrooms, an en suite and a bathroom in the basement, and an open plan living/dining/kitchen area and another bathroom upstairs. All three bathrooms had showers, toilets and sinks. The kitchen had everything we needed to cook (pans, utensils, tableware etc as well as a large fridge freezer, an oven, hob, microwave, toaster and kettle).
There is also a washing machine in the basement. When we arrived the washing machine was broken but I messaged Carolina and she got it fixed straight away. I didn't realise at the time but it was actually a national holiday that day but she still managed to get someone to come out and fix it for us. I've stayed in places with very unresponsive hosts before, but Carolina was very fast with answering messages and fixing problems (not that we had many problems at all). She was an excellent host, making sure we had everything we needed and were comfortable.
I can't recommend this apartment enough, it's a lovely place to stay, in a good location, with great owners. I think it would be a great place for both families to stay and also for groups of friends coming to Madrid for a trip.
The only very minor criticisms I have are that, because they're in the basement, the bedroom windows are very high up and there aren't any curtains, so if you need it to be very dark to sleep you might need an eye mask. The only other thing is that the front door goes directly on to the street and is next to the main entrance for the building, so when you're in the living area you will hear talking outside and people coming and going. This wasn't a problem for me as it wasn't very loud and the windows are frosted so nobody could see in, however some people might be more sensitive to the noise than I am. I don't think either of these things are big problems and neither would put me off coming back again.
Overall I was very impressed with the apartment and hope I can come back again!