Arranged rent and MOT? Agony! (7)
I believe the answer is:
torment
'agony' is the definition.
(synonyms)
'arranged rent and mot?' is the wordplay.
'arranged' indicates anagramming the letters (letters rearranged).
'and' means one lot of letters go next to another.
'rent' after 'mot' is 'motrent'.
'motrent' anagrammed gives 'TORMENT'.
(Other definitions for torment that I've seen before include "Great suffering" , "Hound" , "Tease unkindly" , "Inflict pain on - pester" , "Severe physical or mental suffering" .)