Very roomy apartment, easely houses 4 couples comfortably (two bathrooms) and room to spare. Somewhat sparingly but well furnished with all necessities for a longer stay . On top a wonderful quiet terras to enjoy your breakfast or dinner. Private, though tiny lift to apartment on 4th floor ; indoor stairs to second level / terrace. Situated in lively neighborhood, ( shops, cafes restaurants) but well insulated from outside traffic; quite within walking distance of Metro station (busstop on doorstep ) and some of the more important touristic sites like cathedral and royal palace. Bit of a puzzle to get to Prado/Thyssen/Sophia by public transport.
On the negative: a sometimes strong sewerlike smell when entering the building ; but that seems to be a Madrilene quality you will meet almost everywhere.

Owner Bo is an interesting man, an onobtrusive but great 'landlord'; very knowledgeable about Madrid, very helpful, fluent in English and Spanish, made our stay easy as pie.
We'll be back!!