Unfortunately we had a stressful and uncomfortable stay.
The first night the apartment started getting cold, so we contacted an associate of Federico's who had introduced us to the apartment. They instructed us to adjust the settings.
The next morning it was still cold, so we called Federico directly. He said it was a problem with the boiler that would be easy to fix. He couldn't come help because he was out of town, and he didn't want to call a mechanic. That easy solution involved standing on a chair, precariously placed on a stair landing, and reaching up to turn a dial on the boiler (an adjustment that is not recommended by Italian law). At which point hot water started spewing out all over the floor and my partner's hands, almost burning her! Federico told her she wasn't doing it right, and had her put her hands back into the hot water and turn the dial further. The water changed to a steady stream, which she got a bucket to handle, and over the next couple hours had to clean the floors and chang the bucket frequently.
Water kept coming out, the pressure on the boiler was 0, and there still wasn't heat. Later in the day, Federico eventually came himself (no mechanic!) and changed some settings on a complicated temperature system involving multiple dials throughout the house to enable heat -- none of which is explained in any of the Airbnb check-in materials.
He claimed it was okay for the boiler to have 0 pressure, I really hope he's right and it isn't dangerous to stay there. He told us patronizingly that we should have called him the first night, rather than his associate because then he could have come right away, instead of when he was birdwatching. Then he proceeded to blame us for the issue, saying we shouldn't have changed the thermostat without asking -- which was extremely frustrating given that we had done so following the instructions of his associate.
The apartment was also not very clean when we arrived. There was dust everywhere and a dirty sock on the floor in the living room.
This is a good spot for a short stay among an amazing collection of sculptures and paintings. Just hope you don't have to deal with any of the old appliances that aren't explained, or interact with Federico _whatsoever_. I'll certainly be avoiding doing so.