It was a nice experience. I was greeted by Miguel's sister, who was such a sweet lady. She doesn't speak much English, but she tried her best to help me. The apartment was very well equipped-kitchen with plenty of utensils and basic ingredients, comfy beds, etc. The apartment also has a lift, which was very convenient. The location is great, about 15min walk to Sagrada Familia and two bus stops to a giant Carrefour.
There are two downsides to note, though. First, the tidiness is left a lot to be desired; it was not unbearably filthy, but surely it could be better. The sofa was a tad spotty, the bathroom rug was a little dirty, it was a bit smelly because of the undried mop in the balcony. Second is hot water issue; the hot water is intermittent, presumably due to the boiler. You should make sure you don't take a shower for too long, since you have to wait for quite some time once the hot water is depleted.
Overall it was a nice apartment, good value for money.