Thanks a lot for your stay with us.
Yes, our apartment is at the centre of the city. If you open the doors there is noise, we think that it is usual in all the cities. If you are looking for peace an not noise, we recommend you to look for an accommodation in the countryside, not in an important city like Barcelona.
By the other hand, we think that you have a wrong concept of AIRBNB. In AIRBNB there are accommodations where live owners and they rent their homes, and there are accommodations, for example apartments just for renting.
About the check out, we always check that the apartment is right.
We will ask to AIRBNB to investigate you, or better to explain you, what is AIRBNB. If we can help you with more information do not hesitate to contact us. Best wishes!!