I work for Mattel and that is not a $1500 doll. The only doll that we made that retailed for around $1K was the Pink Splendor Barbie, but that was a ceramic doll and came out in the late 90's.
That particular doll can be had on eBay for around $35 or so. There a ton of Barbie collector sites out there which will give you an idea of what the dolls are worth, but ultimately they are only worth as much as someone is willing to pay for them.
The problem you might run into is in the early 2000's, Mattel saw how much collectors were making from the limited edition "collector" dolls and wanted a cut for themselves. So, they saturated the market thinking they could cash in on some of that action, when ultimately they drove the price waaaay down on these dolls and pissed off many of the big time collectors. They learned their lesson a few years later and have limited production again.
Hope you can make some fat cash on those things. My boss has around $45K in Barbies and my mother-in-law about the same, and they have financed vacations and cars with the sale of those things.
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