We stayed 7 nights at Ludo's apartment and really enjoyed it. There's no window, that's why we thought it might be quite dark. But it was ok, very cozy and nice apartment, comfortable for 3 people. The only one minus is noise from the street early in the morning because of the very thin walls I think. But it wasn't a problem for us.
Metro and bus station is 2 minutes walk, supermarket 1 min. Very close to Plaza Espania and railway station Sants.
Wi-fi was really fast on the first day, but all the next days it wasn't so good.
Overall I would recommend this apartment for everyone visiting Barcelona! Ludo thank you for your hospitality and responsiveness!