Hello :D It’s hard to say since a lot of rare and popular prints pass through. The rarest ones are always the hardest to get since they’re usually bought as soon as they’re put out on sale (e.g. Elizabeth Bride of Death/Gloria, etc.). You pretty much have to be in the store when they’re put out in order to buy them.

The most expensive one I’ve seen in person so far was a recent Toy March set for something like 44,800 yen. A friend saw original Misty Sky at around 66,000 yen once. I’ve never seen Cat’s Tea Party though, sorry. (;_;)