I have just sold two lots of clothes to the same lady and I offered combined postage in my original advert. She paid straight away (before I could send an ammended invoice with a new postage price). She then emailed asking for a combined postage reduction. I have now posted the bundle, but there was no saving as the bundle was so heavy. She paid £7.75 postage and it cost £7.62.
I feel obliged to offer her a saving but there wasn't any. What would you do?