We are an Australian family of four, kids aged 6 & 9. We stayed for four days in June at Mar's first class apartment which was very clean, secure (4th floor with excellent locks) and well equipped. It would sleep six very comfortably, and could manage eight. It is beautifully renovated and furnished, and extremely well located near cafes, supermarkets and attractions etc. (not that it is a large city to get around). As to be expected with any well located apartment in Barcelona, there is a fair amount of traffic at times, although our kids slept very well each night. Mar is a delight and obviously appreciates the importance of ensuring her guests enjoy the experience.