When someone says it cost “an arm and a leg” to gain possession of something, they usually mean it cost more than it was worth in the long run. The expression became widely known during the Depression era but its roots are deeper than the 1930s.
It grew out of 19th century American slang expression “if it takes a leg” which meant that regardless of the price, there was desperate determination involved in securing what the person wanted.
George Pickering‘s book “Memories of the United States Secret Service” published in 1872 provides this sentence:
He goes straight to New York, and will have satisfaction out of these villains, if it takes a leg, or the last dollar he has in the world.
The local Horicon, Wisconsin newspaper called the Horicon Argus published a story on February 17, 1860, in which it reported that:
The true Republicans … are bound to have him defeated if it takes a leg.
There are those who will claim that the earliest known published use of the expression “an arm and a leg” dates back to 1956, in Billie Holiday‘s autobiography “Lady Sings the Blues.” In her biography, she wrote:
Finally she found someone who sold her some stuff for an arm and a leg.
Seven years earlier in a cartoon published by the Nebraska State Journal on October 3, 1949, the caption read:
It never fails! That new wardrobe that costs an arm and a leg … 85 fish! Wow! That’s more than I figured on spending but I guess it’s worth it! Wrap it up!
So the expression, in its entirety, has been around some 60 years at this point.
Historically Speaking 