Aury is very nice host, she provided us with some tips what to see in Madrid.
She even let me borrow her purse. :) The apartment is located close by to the center and only few minutes from metro station. By walking it´s about 20-30 minutes from the main things to see. I recommend you to stay with Aury. Only one little thing, maybe bring your own slippers if you don´t like cold feet but that´s only a suggestion. :)