We spent 4 nights at Paolo's place, and really enjoyed our stay. This is the first time we've travelled with a baby (10months old) so we learnt a bit about what we need and what we'd like in a place.
For a couple (no baby): this place is great, spacious with multiple rooms and everything you need. The location is fantastic, walking distance to everything, great cafes nearby and shops too for groceries. There's great nightlife close by too, and this place is everything you'd need for a stay in Bologna. Paolo gave us some great local tips, and was kind enough to facilitate an early check in for us as we arrived on an earlier flight. Everything was as you could want, and i would highly recommend it.
For a couple (with baby!): there are a couple of challenges. The single access to both bedrooms means when baby sleeps you lose a large amount of useable space. The vibrant area = tough conditions for baby sleeps both during the day, and the early bed times make it challenging. There was quite a bit of noise in the evenings - at entirely reasonable times, but with baby going to bed around 6:30pm it proved slightly difficult.
All in all, a lovely stay, and any difficulties we had (above) were a function of our baby's needs rather than any issues with the place. I would definitely recommend Paolo as a host, and the apartment as a great base in Bologna.