Our stay at Marcs' place was great! He is a very nice host, replies quickly when you text him and is ready to help.
Location: the flat is located in a pretty quiet neighborhood, but with lots of restaurants and supermarkets around. There is also a Lidl right around the corner which is very cheap and quite vegan-friendly supermarket! If you want to go to the city center it will take you around 20-30 minutes traveling, but instead you will have a very clean beach in 10 minutes walking where there are ussualy not many people.
The flat:
Living room is very nice and clean. The bedroom is a bit small, but enough for a short stay for 2 people. It's a bit dark though, but you will probably also not stay at home too much when you visit Barcelona :)