If you think it costs 30% of every sale to provide that service, then I disagree with that, strongly. 3%, MAYBE. Maximum. See my reply to your sibling commen

If you think it costs 30% of every sale to provide that service, then I disagree with that, strongly. 3%, MAYBE. Maximum. See my reply to your sibling comment for a more detailed explanation of my perspective, if you wish. Makes no sense to repeat it here.