Sale item bringing in old money (4)
I believe the answer is:
loot
'money' is the definition.
(loot can mean stolen money)
'sale item bringing in old' is the wordplay.
'sale item' becomes 'lot' (item for sale at auction).
'bringing in' indicates putting letters inside.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'lot' going around 'o' is 'LOOT'.
(Other definitions for loot that I've seen before include "Plunder and ransack" , "Pillage; money" , "Tool found among plunder" , "Burglar's takings - pillage" , "Booty, spoils" .)