In retirement, realise half a mil possessed advantages? (5)
I believe the answer is:
edges
'advantages?' is the definition.
(edge is a kind of advantage)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for edges that I've seen before include "Borders, rims" , "Outside limits" , "Outer limits" , "They're used for cutting" , "Boundaries of a surface" .)