Absolutely amazing :) The room and the flat itself were clean and quite stylish. I had fresh bed linen and towels ready (and amazing coffee in the mornings :) ). The location is great, most of Barcelona attractions are reachable within 15 min on the metro (which is about 5 minutes walk); the beach is no more than 15 min walk from the flat. There's a Lidl and a Domino pizza (where they speak English which was a bonus) within 5 min walk.
Marko himself was really friendly and helpful with any information I could've needed.
The place definitely will be my choice again if I am visiting Barcelona :)