Agreed - occupations were not always consistent.
My challenge is that a John Costain and a Martha Crebbin were definitely my Ggrandparents and these are the ones I'm finding hardest to verify.
Interestingly, on the marriage certificate, John Costain was a seaman whilst his father William was a mariner, subtle differences in description of their seagoing positions.
Thank you for your website, by the way, it has helped me enormously to find lots of relatives and marriages I hadn't' discovered anywhere else.