I spent high school & college working in a gift shop, which is where 75% of all this collectible crap comes from. I vividly recall the craziness of the Walt Disney Classics Collection, which was a hand painted ceramic collection. Not cheap plastic junk for sure, but seriously overpriced, and then the craziness began. Each story had several pieces, but only one piece was a limited edition. To further add to the nuttiness, the year of production was characterized by some icon embossed into the bottom of the piece. We would get calls from all over the US, asking if we had Cinderella's dress w/the wheel icon. My boss took full advantage of the situation and would only sell the limited piece if you bought all the other pieces too! People snatched them up anyhow, I would ring up thousands of dollars in this stuff, and that was in the late 90's.
I can't recall the other special pieces, but the special piece for Bambi retailed for $195, and went for 10x that when demand went nuts. Cinderella's dress has similar margins, from $300 to $3K. I did meet one couple who acted quickly, and purchased several dozen Cinderella's dresses before the retailers began demanding the entire collection be bought along with it, and they quickly liquidated their inventory on this new-fangled website called Ebay. I hope they reached FI a long time ago!
I just did a quick search on Ebay, and that dress has auctions asking as much as $1,600, but the solds show anywhere between $400 - $800. Minus shipping & fees, hardly a worthwhile investment!