Bill a small company for sauce (7)
I believe the answer is:
tabasco
'for sauce' is the definition.
(Tabasco is an example)
'bill a small company' is the wordplay.
'bill' becomes 'tab' (a tab is a bill at a bar).
'small' becomes 's' (abbreviation - e.g. clothes size).
'company' becomes 'co' (abbreviation).
'tab'+'a'+'s'+'co'='TABASCO'
(Other definitions for tabasco that I've seen before include "Hot sauce made from capsicums" , "ASBO Act (anag) - hot stuff!" , "Hot peppery sauce" , "Mexican state; pungent sauce" , "Chilli sauce" .)