Carter was almost hopeless case (7)
I believe the answer is:
wagoner
'carter' is the definition.
(I've seen this before)
'was almost hopeless case' is the wordplay.
'almost' means to remove the last letter (most of the word but not all of it).
'hopeless case' becomes 'goner' (I've seen this before).
'was' with its final letter removed is 'wa'.
'wa'+'goner'='WAGONER'
(Other definitions for wagoner that I've seen before include "Driver of cart" , "Carter" .)