Bargained or negotiated (8)
I believe the answer is:
bartered
I believe this is a double definition.
'bargained' is the first definition.
('barter' can be a synonym of 'bargain')
'negotiated' is the second definition.
(bartering is a kind of negotiating)
(Other definitions for bartered that I've seen before include "Haggled over" , "Exchange goods without involving money" , "Exchanged goods without involving money" , "The - Bride (Smetana opera)" .)