Firstly, I can't speak highly enough of Mirko as a host: he's incredibly accommodating and a great communicator. We had no issues with checking-in and Mirko checked up with a message mid-stay to ensure everything was okay. He speaks great English also.
With regards to the flat: it is a lovely space with great kitchen facilities and a comfortable sofa bed. We appreciated the additional extras such as cooking oil/herbs, teas, coffee etc. There are clear views of the river / rooftops and the historical centre is 20 minutes walk over the river. I would advise just walking from the a train station (~15mins) if your luggage is small as the buses get rather busy. Elevator is a life-saver as there are quite a large number of stairs otherwise!
Thanks again Mirko :)