I have some AMT/ERTL unbuilt models too, al bought in the nineties.
I never bought two of the same kind, except in two cases: the Enterprise-A, because at the time there was no model of the Reliant and I thought I would kitbash one. Never built either one (but someday I intend to).
Also I have 2 Ktingas because the first one I built sucked. The 2nd never got out of the box.
Such modeler I am....
aaaand here they are:
, no Flickr
Here's my attic:
And add to that "one of each" on the on-deck pile in the basement, plus at least one case each of Polar Lights' 1/1000 TOS and Refit. It's... a sickness.