Originally Posted by kemasa
Sales tax on the FFL fee is required if the firearm is subject to sales tax, which in the case that you describe applies. So, you should be paying sales tax on the $40, as well as the total cost of the firearm, including shipping.
Sometimes there is tax on labor/fees per the CA BOE.
Thanks for the education on that. Nickel and mofo dimed living here in CA. They exact their pound of flesh from us at every turn.