The most common and most likely answer to this crossword clue is the 6 letter word HAGGLE
I've seen this crossword clue in Financial Times
H
A
G
G
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More clues leading to the result HAGGLE
Buddy explains!

The straight part
We know that "bargain" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bargain = haggle.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does HAGGLE mean?
HAGGLE verb- To argue for a better deal, especially over prices with a seller.
- To hack (cut crudely)
- To stick at small matters; to chaffer; to higgle.