Yes, there were many dollar coins with errors. One of the best known dollar error coin was the Sacagawea dollar coin and Washington quarter mule error. Only 12 of these coins were made and they can be up to $100,000.
There are 100 cents in the Australian Dollar. That can constitute - 20 x 5 cent coins. 10 x 10 cent coins. 5 x 20 cent coins. 2 x 50 cent coins. 1 x 1 Dollar coin. The 1 and 2 cent coins are no longer in circulation.
Answer Bills are like coins. Their value depends on how many of them were made in any given year. If you go to a coin shop with your Ten Dollar bill and it's in good shape, you never know how much you can get.