When it gets hard to find just what one owns (6)
I believe the answer is:
assets
'hard to find just what one owns' is the definition.
I can't tell whether this definition defines the answer.
'when it' is the wordplay.
'when' becomes 'as' (eg 'when I walked' means 'as I walked').
'it' becomes 'sets' (I can't justify this - if you can you should give a lot more credence to this answer).
'as'+'sets'='ASSETS'
'gets' is the link.
Can you help me to learn more?
(Other definitions for assets that I've seen before include "One's valuables" , "Properties that have money value" , "Advantages" , "One's valuable possessions" , "Possessions of material value" .)