Competitor negotiating rent with worker (7)
I believe the answer is:
entrant
'competitor' is the definition.
(someone who has entered a competition)
'negotiating rent with worker' is the wordplay.
'negotiating' indicates an anagram (I've seen 'negotiated' mean this).
'with' means one lot of letters go next to another.
'worker' becomes 'ant' (worker is a type of ant).
'rent' with letters rearranged gives 'entr'.
'entr'+'ant'='ENTRANT'
(Other definitions for entrant that I've seen before include "Participant in competition" , "Competitor; beginner" , "Someone taking part in a competition" , "Competitor, contestant" , "New participant" .)