My grandma gave me a holiday edition Barbie once (I think I was around 6-7 years old?)
I couldn't understand why I wasn't allowed to play with it, and didn't have any other Barbies, so one day I opened it and played with it... Then got in trouble and she refused to buy me any more. Lol. (She switched to porcelain dolls instead... Can't really play with those.)
Now, I kinda wish I hadn't. Not just for the increased value of the doll, bit for the sentimentality too. Buuut, kids are impulsive, and most prefer to play with toys rather than look at them.
I think that if you want to collect them, you should put in a special shelf high in the room where it can be seen, but it is understood that it is t to play with. Or, keep it in your room and she can look at it in here when she wants to. Then when she gets older and no longer cares so much about playing with them, she can have them to display as she wants.
If you don't have an interest in collecting them, might as well let her play! A lone special edition (that is available to he public) isn't really worth much in the end... It's the collections that are valuable... And there is more sentimental value to something that is loved and enjoyed.