Gifting Between States

There was actually a post a couple of weeks back which touched on this (even the same states), but I have a few additional questions.

I currently reside in CA, and was carless for quite a few years. My father, in MO, bought a car last year (2013 Prius C) and is lending it to me. The title is in his name, and it is registered in MO (and will be reregistered on Monday for an additional two years--it said on the renewal that an inspection is not required this year, so that's handy.)

I plan on driving it here in CA for the next couple of months... after which, I am returning it to my Dad in MO early 2018 while my work takes me overseas for a couple of months.

When I get back in the country, we have discussed him gifting the car to me. What is the best way to do this? Does it need to be gifted in MO, or can he just transfer the title to me and when I arrive back in CA I go to the DMV to register right away? Would I have to pay taxes 'cause it's from another state... and at what point should I get a smog inspection?

Thank you!