more then you could give or pay then priceless bodily limbs, that are expensive on black market
"An arm and a leg" is an idiom that means an exorbitant or very high price paid for something. "Jeeze, did you see that they're charging an arm and a leg for a gallon of gas these days!"
An idiom is an expression that has a meaning different from what it literally says. For example, one can say that something expensive costs an arm and a leg, although clearly the point made is different from what the individual words mean.
American slang from 1960's, possibly from Vietnam, meaning 'costing a lot.'
(The idiom means "expensive" or "overpriced.")"That waterfront property will cost me an arm and a leg.""Don't lose that watch, because it cost me an arm and a leg."
Oh yes, that is an idiom. There are no transactions in which someone literally gives one of his or her arms and legs as payment.
get a leg up on
This is not an idiom that I have ever heard. Perhaps you mean an arm AND a leg, which is an exaggerated way of saying something is really expensive.
An idiom is an expression that has a meaning different from what it literally says. For example, one can say that something expensive costs an arm and a leg, although clearly the point made is different from what the individual words mean.
American slang from 1960's, possibly from Vietnam, meaning 'costing a lot.'
(The idiom means "expensive" or "overpriced.")"That waterfront property will cost me an arm and a leg.""Don't lose that watch, because it cost me an arm and a leg."
This leg of mine, do you want to buy it? It costs an arm and a leg.
Oh yes, that is an idiom. There are no transactions in which someone literally gives one of his or her arms and legs as payment.
It costs an arm and a leg
Then you will remain short. There is human growth hormone available, but not much and it costs an arm and a leg.
In brief it seems falsely translated from the common idiom 'to pull someone's leg', which has the meaning "to trick/fool/kid someone". For example: "Are you pulling my leg?" (Br.) / "Are you kidding me?" (Am.)
your leg
get a leg up on
An example sentence would be: "Are you pulling my leg? "