I recommend Petit’SPlace a 100%. Petit is very helpful and kind, the communication went great. His mother (who lives in the apartment) warmly welcomed me and made me feel comfortable from the moment I arrived. She was around quite a bit, but that wasn’t bothering at all - the opposite. I enjoyed my time with her and appreciated her help (and coffee!).
Now let’s talk about the apartment. Yes, you need to walk some stairs, but that’s worth it because the location is perfect! The metro and buses are super close and take you wherever you want to go. The terrace at the apartment is such a bonus, since you can start and end your day looking at Sagrada Familia… Just magic.