I usually recommend more to pay it by year but not everybody can afford it because it is more expensive at the time, but in the long run is cheaper because the monthly payments for a total year are higher than the yearly payment.
All companies or most of them have this option to pay by month and you can get it done automatically getting the charge in your account so you dont have to remember to make the payment.
If you are a teen maybe its better to go under you parents insurance because your rates will be higher in average.
The insurance rates as you should remember depends on a lot of factors and I cant give any estimates, only your insurance agent with all your information can give you your rates right or also you can do it online, for example at this site how much is car insurance.
Good luck with your insurance search and remember than not always the cheapest is the best option, you should also read the terms of each policy to be sure which is the best choice.
