How much is a 2005 nickel worth with a buffalo on one side and a president on the other?

There's no such coin as a "buffalo head" nickel. The coin is called either an Indian Head nickel or a buffalo nickel, but not "buffalo head" - after all, it shows the whole buffalo on the back, LOL!

Buffalo nickels sell for about 15 to 25 cents if the date is worn off. If you want to sell one a flea market dealer might give you 5 to 10 cents.

Buffalo nickels minted from 1913 to about 1925 had a design flaw that caused the date to wear faster than the rest of the coin, but it still took several years for the problem to show up because nickel is a very hard metal. By the time it became a problem and the Mint fixed the design, there were about a dozen years' worth of nickels in circulation that had lost, or would lose, their dates.