I stayed at Casolare Tre Ulivi with my wife and two kids (7 and 5 years old). We had an absolutely wonderful experience. The house is beautiful, more so than in the pictures, and you can see the great care Luca and his family have put into every little detail of the house. The house itself was very clean and we felt was spacious for the four of us. It stays nice and cool when it's hot outside, has mosquito nets on all the windows (very much a plus) and a great shaded terrace to enjoy any meal. Besides the roomy toilet, there's an exterior shower, great from when you're coming back from the beach.
Balestrate itself is also a nice little seaside town. It has a couple of supermarkets and plenty of small shops with great fresh produce and the people are very friendly and welcoming. It also has plenty of places to eat out with great food (at least the ones we went to!). The beach itself is very nice, especially if you're with small kids. It's sandy and quite shallow for a good twenty meters in, with very calm waves.
As for Luca, we couldn't have asked for a better host. He met outside of town and guided us to the house, where he showed us all the amenities and also had a very helpful ready-made explanation of how to get to the beach (both by car and walking) plus a map of the town with a list of restaurants, cafés and shops. He even went to the trouble of suggesting a few places where we could watch the opening game of the World Cup! Whenever we had a question, Luca was always at hand to reply promptly.
All in all, a thoroughly enjoyable experience, I would highly recommend it to everyone and anyone.