What you need to get for your car to register it in Ca. is a California BAR sticker.
I went through the process to get a BAR sticker for a grey market Ferrari 512BBi,
NOT cheap, easy or fast.
You will need all the smog equipment that Kirk Evans recommends. It needs to be installed just to get the visual inspection passed and then it has to be all set up and tuned to pass the actual smog test.
For more info check ferrarichat.com search for BAR certificate.
Here is a link to a post that explains the basic process:
BAR post
Bottom line is I would not buy another grey market car that does not have an existing California BAR sticker.
There is a reason BAR stickered cars demand a premium in Ca.
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