No A/C in such a small room is a very bad thing to have when you're travelling in the hot summer of Croatia. The consequence of it is that you have to constantly use the standing fan, humidity is your friend in both the main room and the bathroom (with humidity smell) and you can't afford having something to dry (not pratical after the beach!). Well, thwre was no possibility to hang something to dry.
The sofa/bed is only good for young people who don't care about comfort. If you like a comfortable bed to sleep, then it is not the good place for you.
By the way, the picture of the room that you can see before booking is probably the picture of the roof room. We were in the ground floor room, hearing people going in the upper room and hving only a small window giving directly on the street - not good for privacy and noisy.
So on the whole not a recommendable place to stay.
Sorry to write that because the personal in the hotel was very friendly and helpful. The real hotel Angelo d'Oro (not the Santa Croce Rooms) looks very nice but seems to me to be a little bit expensive.
And Rovinj is a beautiful city!