Answer:
A big shiny black car nobody wants to be a passenger in.
A king wears one on his head.
No matter how little or how much you use me, you change me every month. What am I?
What is often returned, but never borrowed?
This is a plant named after a light source. What is it?
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.