Is salesman turning up on street last? (7)
I believe the answer is:
persist
'last?' is the definition.
(thesaurus)
'is salesman turning up on street' is the wordplay.
'salesman' becomes 'rep' (I've seen this before).
'turning up' says the letters should be written in reverse.
'on street' becomes 'st' (I've seen this in other clues).
'is'+'rep'='isrep'
'isrep' written backwards gives 'persi'.
'persi'+'st'='PERSIST'
(Other definitions for persist that I've seen before include "Continue in spite of difficulty" , "Continue in spite of resistance" , "Refuse to stop" , "Continue despite opposition" , "Endure" .)