fictionwise number crunching

Yes, I'm sad and I play with spreadsheets.
I'm also not a genius; believe these numbers at your own risk.

For the last 3 years, fictionwise has had a valentine's day sale, running for about a week eitherside of valentines day. By virtue of the fact that I'm ready and waiting with my "wishlist", I expect it's not going to happen.
Iif it does, here are some handy calculations for EU buyers... ;-)

If you pay with your card, you'll be charged VAT, at 17.5% ish
If you're really lucky you'll also get a per-transaction charge for paying overseas.

So, here are some possibilities, using Gaiman's Stardust, which is listed at $6.99.
Now, let's assume you are a buywise member.
This already gives you 15% off, so the price comes down to $5.94.
You also get a 5% rebate, because of the format, so your end cost is about $5.64. (£3.25)

If you pay by paypal, that's all there is to it.

If you pay by card, you'll get VAT slapped on top of the $5.94, so your total cost is $6.98.
Then you'll get a £1 charge (if you bank with LloydsTSB, don't know about others) so your total cost is going to be in the region of $8.75 (about £5)
Since the paperback costs £6.39 through Amazon, that's still a good price.

So, in conclusion: £6.99 = £3.25 by paypal or £5 by card)

Next tip, regarding rebates.
Suppose you have, like the cleversticks you are, loaded your account up with $18.10. It's a strange amount, but bear with me.
You want to buy two books at $6.99 and one at $7.99, with a total cost of $21.97
Apply the 15% discount on the total and you're goign to have to pay $18.68, right?

Not if they have a rebate going on.
a $6.99 discounts to $5.94
a $7.99 disounts to £6.79

If you buy the two £6.99 books first, you'll have:
$18.10
-$11.88
=$6.22

+$0.59
=$6.81

7.99 @ 85% = $6.79

So you have enough to buy all three books. Yay!

Now, buywise membership costs $29.95 per year.
You immediatley get a free ebook, worth upto $10 - this generally means a book worth $7.99.

So, you've still got $22 to save, if you want to get your money's worth.

So. Suppose you-as-non0member buy stardust at $6.99
you get a rebate of $0.35, so it really costs you $6.64

As above, it would costs a member $5.64

So, essentually you're saving a dollar a book.
If you buy more than 22 books per year then, it's worth signing up.

Howabout EU members? Well.
$29.95 plus VAT is $35.19
The $7.99 free book would have cost you $13.98
So you have $21.21 to save

As a nonmember, stardust costs $8.21
minus rebate; $7.86

As above, it would cost a member $6.98.

So, you are saving about $0.88

21.21/0.88 = about24

So EU members need to buy over 24 books per year to gain anything.

I can't get my head around the bank fine bit ;-)

(If there are proper mathematicians reading, please correct me!!)