That sounds incredibly expensive to me, even PayPal is cheaper (https://www.paypal.com/cgi-bin/webscr?cmd=_display-receiving...).
Source: https://merchant.paypal.com/cms_content/US/en_US/files/merch...
While we're talking about PayPal, if you want to do small transactions there's a special micro payment account with fees of $0.05 + 5%. Works out cheaper for payments < $12. It was hidden somewhere, not sure how I stumbled across it.
http://www.paypal.com/IntegrationCenter/ic_micropayments.htm...
(and yes I do realize that it hurts to see those costs the first few times you make a sale, getting upset over costs like this is the hallmark of the noob internet businessman - it'll pass. Wait until you get your first bill for a nonsense legal issue or pay a 100k settlement for which you know you're in the right but for which you also know that going the length will cost more. Those are the times when it will hurt even more than this.)
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There was/is a bunch of stuff which was completely different from the publiched docs, and all of it was know to the support staff. Seems to me a bit bureaucratic to have know issues which haven't found their way to the official docs.