cash on the barrelhead
Immediate payment, as in They won't extend credit; it's cash on the barrelhead or no sale. The lexicographer Charles Earle Funk surmised that this term originated in the days when upended barrels served as both seats and tables in bars, and customers were required to pay for their drinks immediately, literally putting their money on the top (head) of a barrel.
Words nearby cash on the barrelhead
cash letter,
cash limit,
cash mob,
cash money,
cash on delivery,
cash on the barrelhead,
cash ratio,
cash register,
cash up,
cash value,
cash-and-carry