We spent 5 days at Alberto's place as a group. He went far beyond his duties as a host and made sure that we had a great time: he booked restaurants for us, gave us "insider recommendations" and went as far as to actually buy fresh fish for us, so that we wouldn't get ripped off at the market. His father and kid were also very warm and nice, and we were happy to meet them. As far the house is concerned, with all those beds and bedrooms there is definitely room for a large group like ours, or even just for a family who want to enjoy some personal space. The living room is large and ideal for group dinners, and so are the kitchen and the outdoor veranda. The area is incredibly quiet, the view is fantastic, and we enjoyed the pool too, even though the water was still a bit cold (end of April). We didn't use them but a functioning fireplace and barbecue/grill were available too.
The only issue a guest might face is the final part of the road to the house, which is steep and narrow. We could run it several times a day with regular (small) cars, but at first we were a bit scared by the bumps. Don't worry!
We definitely recommend the house to any group looking for a comfortable, quiet place to stay in Eastern Sicily.

P.S. : once you are there, try the brioches ("cornetti") from the bar in the closest town, they are delicious.