Correct - its determined by the point of sale (delivery location.) IIRC Fremont is 9.5%, other CA locations may be 6.0-10.0%. That's even higher than the combined rate for NYS/NYC (8.875.) In theory you get credit for the sales & use tax if you register in another state, but very few places will have a higher S&U tax. And no, you don't get a refund if your state is lower.
And not all states will give you the credit for taxes paid on other states. Most do. Not all.