A Nickel or a Dime
Used when someone is trying to take more than their fair share and you're like, 'No, you're getting the short end of the stick here.'
"You want two nickels for every dime? I'll take the dime and leave you with the nickels!", Jake, during a deal
"You’re asking for more than your fair share.", My friend, during a negotiation
"You want more than half? I'll take the whole pie.", Me, at a pizza place"