As crude as a second-hand vehicle (4,3)
I believe the answer is:
used car
'a second-hand vehicle' is the definition.
(I've seen this before)
'as crude' is the wordplay.
'as crude' anagrams to 'USED CAR'.
Though, I'm unsure how the anagram is indicated.
'as' is the link.
Can you help me to learn more?
(Other definitions for used car that I've seen before include "Second-hand motor" , "Second-hand vehicle" , "Previously-owned motor" .)