Six: two to screw in the bulb and four to testify that it was lit from the moment they began screwing.
None; the bulb will change itself when it is ready.
I dunno exactly, but my brother's girlfriend's father's boss's secretary's sister's next-door neighbors' priest's cousin's union shop steward's uncle's Knights Of Columbus club Sergeant-of-Arms's nephew's best friend did it real cheap for me once.