would give your right arm for something/to do something
give (one's) right arm
A figurative phrase that highlights one's interest in having something or eagerness to do something. A: "I'm going to the concert on Saturday!" B: "Aw man, I would give my right arm to have tickets to that!" I would give my right arm for your sister's gorgeous hair!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
would ˌgive your right ˈarm for something/to do something(informal) want something very much: I’d give my right arm to own a horse like that.
Farlex Partner Idioms Dictionary © Farlex 2017