Like grass family doctor brought in, it’s negotiable (6,5)
I believe the answer is:
asking price
'it's negotiable' is the definition.
'like grass family doctor brought' is the wordplay.
I cannot quite see how this works, but
'like' could be 'as' and 'as' is present in the answer.
'grass' could be 'rice' and 'rice' is found in the answer.
'family' could be 'kin' ('kin' can be a synonym of 'family') and 'kin' is present in the answer.
'doctor' could be 'gp' (general practitioner) and 'gp' is present in the answer.
This accounts for all the letters.
This may be the basis of clue (or it may be nonsense).
'in' is the link.
(Other definitions for asking price that I've seen before include "Sum at negotiation start" , "Amount for which item is offered" , "how much is wanted initially?" , "Value for sale" , "At which something is offered for sale" .)