Absolutely stunning location. Lounging on the patio in the hammock was fantastic. Only two things to keep in mind: 1. Very few people actually live in the Old Port, it clears out after the cable car stops running and felt pretty deserted. 2. This is where the cruise ships let people off in the mornings so if you time it poorly you might be waiting in a very long line to get up to Fira using the cable car.
That being said I still loved my stay and it was the most unique Airbnb I've ever stayed in.