What a thread this turned out to be. I'm a friend of Yannis and I have to admit that yes he did the wrong thing here by not completing the sale with Matt. Once a deposit or payment has been made and agreed upon, then the book should no longer be for sale. It's a done deal. I'm sorry that Matt wasn't able to get the book he saved up for, but I'm sure in time he would have the chance for another copy. Having been lucky to own 2 copies of the book, I think he will get it and I too will help him find the right copy for him.
I also do not think that Yannis deserves to be in the probation thread as he didn't keep Matt's deposit nor cursed anyone on the boards. I believe the probation thread is for more bigger and serious things.