House I head -- I love upsetting common folk (3,6)
I believe the answer is:
hoi polloi
'common folk' is the definition.
'house i head i' is the wordplay.
'house' becomes 'ho' (abbreviation for house).
'head' becomes 'pollo' (I am not sure about this - if you are sure you should believe this answer much more).
'ho'+'i'+'pollo'+'i'='HOI POLLOI'
'love upsetting' is the link.
This may not be right. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for hoi polloi that I've seen before include "commoners" , "The plain people in Greece" , "The common people generally" , "The unwashed masses!" , "(Often derogatory) term for the masses or common people" .)