Rentman involved in scrap (7)
I believe the answer is:
remnant
'scrap' is the definition.
('remnant' can be a synonym of 'scrap')
'rentman involved' is the wordplay.
'involved' indicates an anagram (involved can mean confusing or complex).
'rentman' anagrammed gives 'REMNANT'.
'in' acts as a link.
(Other definitions for remnant that I've seen before include "offcut" , "rest" , "faithful minority" , "Piece of cloth left over" , "Piece of leftover fabric" .)