We had a really amazing short stay in barcelona. The apartment is so cosy and located perfectly in the middle of el barrio gótic.
The flat was super quiet, with a small balcony out the back. It had everything we needed, well equipped. 2 bathrooms and a comfortable lounge to gather. Everything was super clean. As it is in a big house with mostly locals living there, it is so important to respect the rules. They will appreciate you not being too loud.
Once you step out of the house, you are in the heart of Barcelona with plenty small restaurants and bars within walking distance. Even la barceloneta (beach) is only a 20 minute walk. Las ramblas is just around the corner.
I would definitely recommend to stay there, brilliant for a relaxing getaway!