First of all, I highly recommend renting Paolo's flat.
About the flat:
The flat was extremely clean, perfectly located (1min walk to the Colosseo and it's Metro station) and matched the description.

About Paolo:
However, it was Paolo's effort what took our Rome experience to the next level. Before heading to Rome, he provided us with lots of useful information after knowing our main interests, for example which typical Roman dishes we have to try, his favorite museums, untouristic quarters with flair etc.
When we arrived, he picked us up at the Metro station and showed us a little bit of the neighborhood. Paolo was really good prepared and gave us a map, on which he marked good restaurants, places with a great view or where we should get the tickets for the Colosseo. This helped us a lot to get a first overview. By the way, the restaurants he recommended were really good.
Additionally, he provided us a bottle of white wine, coffee, toast, marmalade and fresh fruits.
During our stay, he has been available per SMS or airbnb app, for example to tell us the best way to the Vatican and the approximately time we would have to take.

Concluding, I can't think of a single thing we missed during our stay.
Thanks Paolo for the great time!