Exact prices fluctuating one point (7)
I believe the answer is:
precise
'exact' is the definition.
(I know that exact can be written as precise)
'prices fluctuating one point' is the wordplay.
'fluctuating' indicates an anagram.
'one point' becomes 'e' (compass point).
'prices' with letters rearranged gives 'precis'.
'precis'+'e'='PRECISE'
(Other definitions for precise that I've seen before include "Recipes (anag.)" , "Detailed, exact" , "with accuracy" , "Express" , "'Exact, accurate (7)'" .)