I won't try to claim I have the codes at my fingertips... but if you think about it for just a minute...
If all you had to do is buy your guns out of state, their little safety list for handguns would be worthless wouldn't it? All you would do is step into NV or AZ and it would be easy.
It hasn't been easy to see exactly how to bring in guns which are transferred from family or inheritance for example, so rather than risk my list falling into some politicians hands, I stopped trying and left them far from here with my attny.
At that time, they had not yet banned many of those handguns, and it was still going to be difficult.
Now, I would hesitate to guess, but if I were to guess I would assume if the handgun isn't a model on their approved list it would be rejected regardless of how you came to posses it. If it is approved on their list, it appears that I would have had to go through a submittal of what amounted to the same level of documentation for a new purchase. This was all based on what I saw as hurdles to an inheritance and I passed on the risks.
As far as getting other types into CA, they mostly all come to your FFL before you get your hands on them and that gives you a chance to address "evil features" before you take possession (for example, bullet buttons, flash hiders, large cap magazines, etc.)
Out of state must follow the same if they are taking up residence. Passing through town or state is different than living and working here.