We enjoyed our stay in this apartment. The best parts about it were the patio, the location felt safe and convenient for eating out and also a short walk to Sagrada Familia. There is a washing machine but no dryer. The building has a small elevator. This district is perfect if you have kids, it feels safer than the Gothic district but it's further away from most things you may want to do.
There are 4 bedrooms but only 3 have air conditioners in them. There is also an air conditioner in the living room and you can keep cool unless you want to use the bunk bed room. The hosts are very nice and quite responsive which was great. We requested 2 cribs and they were able to accomodate that which was a big deal for us. One thing that we really liked was that the curtains helped keep the bedrooms dark which helped us sleep in and recover from jet lag. All things considered it wasn't super noisy in the unit.
There are some things that were not ideal for us and I want to mention them in the review. First of all the check in. We were after hours and there was an electric scanner for our passports. We had some trouble with it and had to manually type our information in. The check in instructions said we had to put in all the passport information including for kids but the machine was giving us an error that the date of birth was not valid for minors. We were able to message the host and get a key and complete our registration in person the next day. Beyond that the air conditioner in the room we stayed in made a fairly loud rumbling noise every 15 minutes or so which made it hard to sleep. We had our family and my mom staying in the apparentment and I definitely felt there was no privacy and very close quarters. The bathroom was small and there was no counter space. There were 2 side by side showers but each was very tight and it was hard to shower without getting water on the floor. Also when you shower the metal part that you use to turn it on gets very hot. Be careful of that if you have kids.
Overall, I would still reccomend this as a place to stay for families looking for a safe location close to a lot of restaurants and close to Sagrada Familia