The shipping blues

About a month ago I decided to sell some toys. One of these toys were the "Ice Cream Twins" transformers from the ROTF toyline. They're recent, in good condition and I fucking despise the toy and the characters they're based on, so naturally they were one of the first things to be bought.

I got a guy saying he'd pay me Via Paypal, 9$ for the pair. I thought that this sounded fine, got ready to ship, sent him an estimate, and....

Nothing.

He disappears for two weeks, then sends me an email saying he's still interested. I tell him I have some new stuff, and he buys two more things, for a total of 21$. I tell him I can ship immediately, but find out Collect on Delivery shipping doesn't work like I thought it did. A couple of days delay, but nothing serious.

So I come home from work, turn on my computer, IMMEDIATELY go to the /toy/ board on 4chan and see someone advertising what they bought today. They bought the Ice Cream twins.
"I actually bought the Ice Cream twins off a fellow /toy/ soldier, which I don't have yet, that I will have to get rid of now. If anyone is interested, I'm willing to sell it for $15 shipped."
I'm slightly irritated. The guy ordered them from me but goes out and buys them from retail anyway? (At this point he's paid me)
So I say
"I can just ship to you without the Twins and refund you what you paid for them."
He proceeds to throw a little hissy fit because they haven't been shipped yet, then he asks me to give him his money back, since he only wanted The Twins.
I tell him (honestly) that the money he sent me is gone. It was for a specific purpose and served that purpose.
Then he emails me back with this little gem:
"Well, the only thing i can do is to ask you to return my money asap. I obviously can't make you return my money but it'll just let me know not to do business with you in the future nor recommend anyone to buy from you. I apologize if i've said or done anything to upset you."

So, I rebuffed with this:
"Y'know, I wouldn't be upset if you hadn't disappeared for two weeks, returned asking for the Ice Cream twins and bought two other TF's you apparently didn't want anyway. I wouldn't be upset if you hadn't proceeded to buy The Ice Cream twins, then demand I pay you back for them and the other things you bought.
I'm not returning your money. I'm shipping what you paid for (minus Scalpel, the money you sent for him will be treated as shipping funds) and making damn sure you understand that you don't do business like this. That two week disappearing act? I can understand. I was relieved to see you email me back at all, let alone still wanting to buy.

If I was in a position to return your money, I would. But I'm not, and I won't be in the near future."

(I just got an email back from him, saying I was charging him 21$ for two figures that he could buy for 15$. In reality, I was basically selling him these things for two thirds retail price.)

This is the only bad experience I've had so far. Other people (like the guy I drunkenly blogged about before) have been helpful, pleasant and generous.

Now I need to go to bed, jesus christ.