If I have a fin, a sawbuck, and four bits, how much do I have?

$15.50

"Fin" (also "finnif") is from "finf," Yiddish for "five," and "sawbuck" refers to a kind of sawhorse with crossed wooden legs, forming an X, the Roman numeral for 10. A double sawbuck is thus a twenty-dollar bill. "Sawbuck" is sometimes abbreviated "saw," but not, of course "buck."
The heavy dollar coin was once known as an iron man, plug, sinker, or wagon wheel. And the old Spanish peso coin could be physically broken into eight pieces, each worth one real, an eighth of a peso; hence the coins were called "pieces of eight," and a 25-cent coin, a quarter dollar, is "two bits."

Yay, Kainantu. That's three for you. Care to try my baseball question?