All states I know of do it annually
Go to the department of motor vehicles or go to their website and renew it.
About $50 in NJ. I think it varies by state.
Go to a NJ DMV office with the old registration, proof of insurance and checkbook. Fill out the forms and the nice people there will give you a fresh document. If no registration exists take the vehicle title with you.
Once a year.
no renewal necessary!
Every three years
every 3 years
evry 2 years
every 2 years