Computer arrangement a depressing affair for person of property (9)
I believe the answer is:
landowner
'computer arrangement' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'a depressing affair for person of property' is the wordplay.
'a depressing affair for' becomes 'land' (I can't explain this - if you can you should believe this answer much more).
'person of property' becomes 'owner' (I've seen this in another clue).
'land'+'owner'='LANDOWNER'
Can you help me to learn more?
(Other definitions for landowner that I've seen before include "Owner of an area" , "Laird" , "One possessing estate" , "One may have lots of grass" , "One with title to an area" .)