When you buy a brand new roketa scooter should you get a title or a certificate?

Since it is technically a "moped" or bike powered by a 50cc (or less) motor, licensing is not required in all states, therefore (in those instances) a "title" will not be issued by the MVD or the dealer who sold you the motorized bicycle type of transportation. You should, however, have a Bill of Sale. See link below for more info.