When I pulled my childhood collection down from my loft in the mid Nineties and started buying more figures, I just mingled them all together.
I was buying up job lots and amassed easily a couple of thousand toys and figures so no way of knowing which were my originals. In truth I'm not super sentimental about them, and would rather have a mint example than a playworn one (even if it was little me that did the playing!).
My Palitoy Death Star however is the one I had since childhood so that's got to be the longest.