My buyer paid a total of $39.60 postage, and I refunded $14.30, so to me it was worth asking.

I have a lot of listings (at least for me it's a lot) now that I can list more than 40 per month.  But I don't sell that much.  I don't make a living on eBay - just trying to shift years of accumulation out of here.  I'm very happy when I do have a sale, as that means a bit more clear space.