I get to have fun at a lot of birthday parties!
I like to show up with something either over the top big or something very special made of balloons for the birthday child. For instance if the theme of the party is Little Mermaid I would bring an almost life size mermaid!
Then all the kids get a balloon creation made for them on the spot. If there is time, we may play a game, Giant NASCAR Racing Ducks is my favorite. I may put a few balloon hats on the adults.
I can outrageously entertain about 20 kids in an hours time and the pricing is, one hour - $150 two hours - $250.