Question regarding purchasing a dirtbike or ATV?

[Josh E]

I have been very interested in motorcycles, dirtbikes, and ATVs since a very young age. I am hoping to purchase either an 08 Yamaha TTR230 (dirtbike) or an 08 Yamaha Raptor 250 (ATV) soon. I live in Southern California, I am 17 years old and have been driving for at least 2 years with no accidents or tickets (and I plan to keep it that way). I have done some research but I still have a few problems and questions.
When I go to the dealership, I am expecting to be paying for:
-the ATV or dirtbike
-proper off-roading gear

I am a bit unsure about the whole registration and insurance process and would like to know how that all works.

I would appreciate if someone could also tell me or give me a rough estimate on how much I will be paying for registration and insurance. Like I said, I am 17, no accidents, and I live in Southern California.

Thank you all for your time.

[Bugs Bunny]

ATVs are very dangerous-- stay away from them. The worst thing is not dying. It's being severely injured.