I read that book over twenty years ago. I think Bellarosa was a composite. It was written during Gotti's heyday, and DeMille is a Queens-Long Island guy. I think he still lives in Garden City. So in my opinion, Bellarosa being so flashy was clearly based on Gotti.

Oh, and the long awaited sequel, "The Gate House," was even more far fetched and ridiculous than the original. At least "The Gold Coast" was a good "beach read."