Property found in toilet at Selfridges returned (6)
I believe the answer is:
estate
'property' is the definition.
(estate is a kind of property)
'in toilet at selfridges returned' is the wordplay.
'in' says the answer is hidden in the clue.
'returned' is a reversal indicator.
'etatse' can be found hidden inside 'toilet at selfridges'.
'etatse' in reverse letter order is 'ESTATE'.
'found' acts as a link.
(Other definitions for estate that I've seen before include "Car with a rear door" , "Extent of one's property" , "Property - may go with rank" , "Nakedness" , "Scheme of new housing" .)