Negotiates to win tip for these servers (10)
I believe the answer is:
bartenders
'servers' is the definition.
(I know this)
'negotiates to win tip' is the wordplay.
'negotiates' becomes 'barters' (bartering is a kind of negotiating).
'to win' indicates putting letters inside (some letters win or obtain others).
'tip' becomes 'end' (tip can mean the end of something).
'barters' going around 'end' is 'BARTENDERS'.
'for these' is the link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Another definition for bartenders that I've seen is " They may serve one a wallop".)