I have over 400 unbuilt kits in my stash. Some were bought to build, some were bought as trans kits, some were bought for parts.
I like having several of the same kit because you may see an orange Fairlane you would like to build while researching the blue Fairlane you're currently building.
Sometimes I'll look though a Hot Rod magazine, I see a picture of a car I'd like to build, but I already have one built. Well since I had two in my stash, I get to build one like the one I've just seen.
I have 4 '70 Mustangs that I've built, along with 4 '64 Fairlanes, etc.
Just my two cents.
Roy the Ford guy