Despite not actually meeting Carolina she was a wonderful host. The automatic check in was a very useful as we arrived at the apartment after midnight due to a late night flight. She was very communicative throughout our stay and offered us useful tips and advise in regards to places to eat and activities such as bicycle rentals and Porto cellar visits.
In regards to the apartment it was as described and as they is appeared in the photos. Everything was nice and clean. I personally made good use of the coffee machine. The apartment and garden area were also very quiet (considering its location).
The apartment is located about 15 minutes walk from the main tourist areas down by the river and about 10 minutes from the bars and restaurants at Praça de Lisboa/ Praça de Carlos Alberto/ University area. There is also the main metro station about 200m from the apartment (which you may find useful as heading back to the apartment is all up hill!)
Overall a very pleasant stay and I would recommend.