When the client feels the invoice isn’t fair enough for the quality of design:.
In the above sentence, I used the word fair for invoice. Basically I want to say that the client feels the quality of design isn't good and still he has been given an invoice with more charges/bill (sorry I don't know correct word).
I Googled the similar use of fair invoice, but couldn't find satisfactory results. I understand the meaning of fair bill, fair deal, fair commenet/question/answer etc. But I just can't say about this use.
So the fair enough for phrase makes sense here?