My friend and I stayed here over the summer for just shy of 3 months.
The flat is just as described. Super clean and well kept. The kitchen was great and had everything we needed to cook our meals.
Having air conditioning was also spectacular, and double paned windows kept the heat and noise outside during the night.
The beds were super comfy and were standard queen and twin size.
The bathroom is definitely on the smaller side, but it was never a problem what so ever.
Access to the terrace on the same level(4th floor) was awesome as well. Fun little outdoor area to have a meal or enjoy drinks.
The location of the flat is about a 2 minute walk to the beach. Surrounded by tapas restaurants, bars, bakeries and grocery stores.
Our host, Spyros was extremely friendly and inviting. He is a good resource on Barceloneta, and much more. If anything arose, he was quick to respond and very helpful.
All in all, it was a 10/10 experience. Would do it again!