The Schwarzschild Radius tells us how big black holes appear to be. No one knows their actual size.

http://en.wikipedia.org/wiki/Schwarzschild_radius

As for our local sun, you can tell him that a lot of people think that its center is composed of a superconducting superfluid surrounding a black hole. Some people think the Earth and many of the solar planets and some moons ( ie IO ) have black holes in them that were created during the big bang.