What is slang word related to, say I ask somebody a 100 pound...

[Storm]

what is slang word related to, say I ask somebody a 100 pound but I already know that I will get only 50 pound...but I try to ask more first. Some slang word start with 'High....

[Mister Micawber]

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'High hopes'?
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Canadian-American native speaker
who teaches English for a living at Mister Micawber's
ESL cafe: Interview with Mr. Micawber

[Yankee]

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I've heard both "high-ball" and "low-ball" used as adjectives (and also occasionally as verbs) to describe overly high or low estimates or offers.

Maybe that's what you were thinking of.
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