This place may well work for some people (the location and the terrace were great), but it didn't work for us and we left after a week (having booked it for 3.5 weeks originally).
The things I would highlight:
1. The third bedroom (accessible by terrace) is not usable in the summer. It has no air conditioning and gets extremely hot. The agency did buy a fan on our request, but it didn't do much and we ended up sleeping on the sofa. That room also has an ant infestation, that did get better after several clean ups (a superficial one by the agency and two thorough ones by us) but did not go away. So expect ants in your luggage, shoes and bed.
2. The main bedroom air conditioning doesn't work, but it does benefit from the ac in the living room / other bedroom a bit, so it was ok on all but the hottest nights.
3. The place is superficially clean so you would be ok for a shorter stay, but the soft furnishings were a bit sad. The soft lounger covers are completely destroyed.
4. The plumbing was temperamental - we had two sink blockages in a week. The first was resolved within 24 hours by the agency but came back a couple of days later, by which time we were leaving.
5. The place is Managed by an agency called Barcelona Best services and I'm not convinced that Rosa exists.
All in all, the place has potential but is vastly overpriced for what it is. I think the owners need a break every a lot of work to justify the price. In the mean time - avoid in the summer months.