Buyer of an electric fan? (4,8)

'an electric fan?' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'buyer of' is the wordplay.
I cannot really understand how this works, but
'buyer' could be 'customer' (I've seen this before) and 'customer' is located in the answer.
'of' could be 'o' and 'o' is found in the answer.
The remaining letters 'col' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...

Can you help me to learn more?