First of all, the room is not 300m from Duomo, but 1km.
We were given the host's room (large, but a bit messy), instead of the booked one, because of another guest early arrival.

I would say it's an interesting and cheap option for backpackers, the house is not immaculate but Marco tries to help travellers with tips about Catania and so on.

Now, the host asked me twice to cancel my booking in order to solve the "overbooking" problem, not understanding I would have lost 100% of what I paid, not offering any other solution (calling customers' support?), so I can't say he's an experienced host.