Car salesman left company at the end, offering email response (9)

'car salesman left' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'company at the end offering email response' is the wordplay.
I cannot quite understand how this works, but
'company' could be 'auto' (auto company is a kind of company) and 'auto' is present in the answer.
'response' could be 'reply' (synonyms) and 'reply' is present in the answer.
No letters remain.
This explanation may well be incorrect...

Can you help me to learn more?