There are two things you need to know:
1. In the UK we have a book called
The Yellow Book. As you can see from the link, it's a list of gardens in the UK that are opened to the public for charity. The proceeds from the book are also donated to charity after the publishers costs. All in, an excellent cause and a great idea. The book retails at £7.99. Very few shops sell it at less than that since it's for charity, but sometimes older editions (they release one a year) can be marked down to £2-£3 ish. They still have a market because a lot of the contents doesn't change very much from year to year and the charity take the line that every little helps with the older editions and keep them on sale until the entire print run has been sold.
2. We have a NO CASH REFUNDS policy. It's been store policy since somewhere around the jurassic period and is CLEARLY marked all over the desk.
So...guy stomps into the shop with one of our paper bags, immediately I'm on alert cos he has that look about him, you know the "I suck" look.
SC : "My wife brought this book *dumps the yellow book 2005 on the counter* it's 3 years out of date, she wants the new one."
Me: "Ok, I have one copy of the new one left, I can certainly swap that over for you, you've already paid £2.99 for the older edition, so it would be an extra £5..."
SC, cutting me off: "I'm not paying an extra £5! That's ridiculous! My wife brought this in error! I want a refund!"
Me, internally sighing: "I'm sorry sir, I can't give you a cash refund, I can give you a credit note or I can exchange the book for something else..."
SC, cutting me off AGAIN: "That's ridiculous! THIS IS OUT OF DATE! I don't understand why it's still on the shelves! You shouldn't be selling something 3 years old! My wife brought this in error..."
Repeat ad infinitum until the wife herself walks in. He shouts that we won't give a cash refund, she, being a FAR more reasonable human than her husband asks me why, I explain it's the store policy and she LISTENS, she's not happy, but she's not kicking off like her moronic other half who is STILL ranting away merrily beside her. She explains that they don't live locally and would have no use for a credit note, I offered her an exchange, she turned it down, said she wanted the new one, but not for £7.99. Then the husband starts up again...
SC: "I want to speak to your owner!"
Me: "I'm sorry sir, he doesn't work out of this office, I can fetch you the manager if you'd like?"
SC : "I've a good mind to rip this *waves book about* up and leave it here as a message to your owners! What do you say to THAT?!"
Me: "Well that's your choice sir."
MrsSC: "Oh look it's only £3, I'll just ring the gardens we're visiting first to make sure they're open. The numbers'll be the same in this edition."
SC: "You tell your owners that we're never coming back here again! They have a great policy for making enemies! *stomps out*
So...lemme get this straight...we lost a customer who :
a) didn't live locally and didn't shop here anyway
b) had spent the sum total of £2.99 in store
c) couldn't read a book title correctly
d) was a total arsehole
I'll be crying in my sleep over the loss of that one eh!
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And then, the bonus moron (BM)! I will grant you, I was having a bad day and he got on my last nerve, but really, I fear words cannot convey the sheer "I want to kill you" feelings this guy inspired in me...hence the slightly more bolshy than usual attitude he copped from me!
BM : *walks up to counter and SLAPS a £5 note down, then stands there and looks at me with the kind of totally insincere "I'm dealing with someone so far beneath my own level of being that it's equivilent to scraping something nasty off my shoe" smile*
Me : "..."
BM : *punchably smug look*
Me : *desperately attempting to stop a brow flickering into hairline* "Can I help you sir?"
BM : "You're going to give me a penny and an Enid Blyton hardback."
Me : *blinks* "Am I?"
BM : "Yes. That one." *points to book behind me on the "hold" shelf with smug, supercilious smile still in place*
Me : *takes card from book* "Would you be Mr.BonusMoron sir?"
BM : "I want to see the book, it has to be the right one. Give me it."
Me : *raises brows and stares him down*
BM : *grudgingly, with a nerve ticking in his jaw* "Please."
Me : *hands over book*
BM : "This isn't the book I asked you to hold."
Me : "It's the only hardback Enid Blyton we have in stock sir."
BM : "It's not the one I wanted." *whips £5 back off desk and storms out the door*
Oh the charm...there are days when I wonder how I manage to stop my knees going weak at the sheer oozing sweet talk I get from these customers!
The Yellow Book & a bonus moron!
That had to be a punch in his ego. 
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