Pawn Stars Questions?

I'm a really big fan of the show Pawn Stars. I know the show has a a lot of staged scenes and there is also some product placement and I was just wonderi? How do they film the show? Also one of their historical experts is the guy who always wears the hat and runs the Clark County museum, why doesn't he give prices for the items he looks at. He says he doesn't do it, but why? Any other things about the show that you wanna throw in your answer would be great!!!!!