Game over for purchase (4,2)
I believe the answer is:
snap up
'purchase' is the definition.
The answer and definition can be both to do with ownership as well as being verbs in their base form.
Perhaps you can see a link between them that I can't see?
'game over' is the wordplay.
'game' becomes 'snap' (card game**).
'over' becomes 'up' (I've seen this in other clues).
'snap'+'up'='SNAP UP'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for snap up that I've seen before include "Purchase eagerly and quickly" , "Unhesitatingly take" , "Grab eagerly and quickly" , "Snatch" , "Quickly accept" .)