Move at the end of August, cheap (6)
I believe the answer is:
budget
'cheap' is the definition.
(I've seen this before)
'move at the end of august' is the wordplay.
'move' becomes 'budge' (to budge is to move slightly).
'at the end of' suggests the final letters.
The final letter of 'august' is 't'.
'budge'+'t'='BUDGET'
(Other definitions for budget that I've seen before include "Fiscal estimate" , "Limit of funds" , "Financial estimate" , "occasion for speech" , "Funding plan" .)