Penny-pinching company secures great deal (6)
I believe the answer is:
cheapo
'penny-pinching' is the definition.
(penny-pinching means cheap or frugal)
'company secures great deal' is the wordplay.
'company' becomes 'co' (abbreviation).
'secures' is an insertion indicator.
'great deal' becomes 'heap' (synonyms).
'co' going around 'heap' is 'CHEAPO'.
(Other definitions for cheapo that I've seen before include "Shoddy" , "Inexpensive and shabby" , "of little value" , "inexpensive and not much good" , "of poor quality" .)